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December 1999 Is it live or is it Bon-Acchord?

“Enjoy the Music” we’ve been told is what hifi is really all about; otherwise it’s just boysie toys. Our committee agreed to Peter’s suggestion to get his friend David to come along, together with three other barbershop quartet singers to perform live for the Club’s Christmas Bonanza. Just the same, it was with some anxiety that the Melbournaires were teed up. Oh dear, what if they’re corny… (that’s the uncool word for uncool)…in these days of computer megadeath who’s going to be impressed by “Sweet Adeline.”? Will the natives get restless and embarrassing?

And as a fee bonus: how fascinating it would be able to (almost) do a direct comparison between reality and recording.

What’s this about choral singing?

Barbershop is a worldwide phenomenon, begun in the US of course, where men sing in four part harmony. A particular, narrow range of distinctive chords is what separates them from other part singing.

Most men would sing “Lead.” That’s how you sing the tune in the bathroom. Easy. Above that there’s the Tenor, whose undies. are too tight. At the bottom is the Bass. It’s the foundation. All ‘real’ men think they sing bass, and can growl down there if they try, but it doesn’t project beyond their shoes. Frank Sinatra or Tony Bennett sing in the comfort range of most men’s voices, or Lead. Below that is the Baritone (called “Barri”) and when he’s getting it right, nobody hears him. Beautiful invisible filling-in.

Actually, that’s the secret of most choral singing, blending. People say “I couldn’t be a choir singer, I don’t have a good voice.” But that’s not how it works. The BeeGees (aka Heeby Jeebies) coalesce. They don’t want people to stick out. If you can blend with the person next to you, that’s ideal. NOTE: Unless they’re singing a different part, then it’s harder. Much. To sing properly, you have to listen hard. Surveys have made a fascinating correlation: communities where people sing together say that they have a better quality of life. Some find Barbershop fascinating and admirable, but nailing “Down by the Old Mill Stream” can be less satisfying than the broader choral repertoire. In barbershop, the fraternal camaraderie is such that you can be anywhere in the world, and get a group going. Everyone knows all the songs.

How do you learn to sing parts? The hard thing is to unlearn the “tune” and you get that by repetition. The best way is to take away a cassette of your part (CD-R nowadays?) prepared by the leader and play it in the car, singing. At traffic lights, people hear you sing “Bye bye Blackbird” and it’s not even in tune. At practice, a piano might thump out your line, and with your section, you try to nail it, to get it into your head while the ones with the easy parts laugh. Darned lead, always putting you off. . Reading the dots is a bit of a reminder too, but they try to get you away from relying on it, to be able to read the conductor’s face and hands.

They get together en masse, but will also split into fours. Women do their own same thing and there’s a CD of “the Sweet Adelines” in shops around town. To get into one of those choruses you need to be able to sing in tune (and before laughing, check yourself by singing “Happy Birthday” out loud as a test.) Most people don’t go up or down the full step, ending up somewhere different from where they should. While practising, the conductor blows a starting note on a pitchpipe, kind of a mouth-organ with just one octave of notes. At the finish, he’ll blow the desired finishing note and the degree of wander from it can be a worry. Or not, and there’s jubilation.

Hearing the full chorus of the Melbournaires in rehearsal, it would be difficult not to be impressed; first the spine-tingling chords, then the “mucking about” with the tempo and dynamics, also the precision of a group in full voice. There’s power there, man! Finally for bonus points, choreography brings contact with the audience, and coaches teach hand and feet movements until they get them off Pat. Pat is one of the best.

Problem: As the meeting approached we were told that David’s quartet from The Melbournaires couldn’t make it. But they could recommend another group, “Bon Acchord, they’re on the Net” On the telephone that’s easy, but try to find them when you don’t know the spelling. Good fun. Bingo! “Would you be prepared to sing for us?” “Sure.” And they agreed to letting us record the event. Phew. Standard practice for arranging General Meetings.

Bring on Bon Acchord

The night arrives, with some trepidation. Will it be refreshing to listen to live music for a change? Yes. Wow!. What a surprise. Stagecraft. Precision. Stunning chords. Most of us were sitting on the front of our seats catching every nuance. What was the best? “Bye bye blackbird” was perhaps the most rewarding (and difficult?). Afterwards, they explained, that piece wasn’t traditional Barbershop. There’s Barbershop and there’s A Cappella (‘from the Chapel’ ) which is also unaccompanied part singing. The second diverges more widely from the traditional and recognisable barbershop harmonies. Anyway, the program, which included “I still call Australia home” done barbershop-wise, the expected oldies, as well as plenty of amiable patter and clever repartee and general bonhomie was a delight to all. Not least the singers, who said, “when you go for a chord and it ‘locks’ and sounds just right, that’s what it’s all about. Ant that night they had more locks than Pentridge.

A Cappella

Perhaps the best known group singing that style would be Manhattan Transfer, and one of their best is “Vocalese” in which they do vocal versions of famous jazz pieces. Then there are the Hi-Lo’s who were top of the pops in the fifties and still devastatingly exciting. They’ll knock your ears off. It’s like classical string quartet music, or like Charlie Parker. His thing was to get more good musical events concentrated into every bar. Check out the Hi-Lo’s on the Net (sorry about the errant apostrophe-but try finding them on the Net without) and more recently, Singers Unlimited. Then there’s a local group with a delicious name, The Banana Blenders (from Queensland, of course). Like everything, there’s an e-newsletter from John Neal, a merchandiser who sells only A Cappella music: called Primarily A Cappella at harmony@singers.com or: e-mail to “Online Buyer’s Club” obc-l@majordomo.singers.com to subscribe, or as they say, Check out our web site at http://www.singers.com

Not quite ALL about recording digitally

A bonus for the night was an attempt to record the group, and even perhaps hear a playback of the result over a hifi system. But we know Murphy.

With Doug’s microphone-audaciously homebuilt-hopefully catching it all in his pocket-sized MiniDisk recorder, and Lucas perched over his infernal IBM machine we had middling-high hopes for something half-decent to come out of the evening. Lucas was taking the same line feed and making a file direct into his computer. “Direct-To-Disk.” Bold. Fruitless, alas. After saving 100 Megabytes of musical information (but before the end,) Windows flashed the extremely user un-friendly “Blue screen of death.” His machine said “enough” as it couldn’t keep up with the Analogue to Digital conversion and writing it to memory. Everything was lost, sad to say, but would Digital Doug come through with the bits?

Doug Digs Digital

He sure did. “I have here in my hand a tiny disc (a MiniDisk) which has captured very bit of tonight’s performance. Anybody want to hear it?” Y-E-S! Was it any good? YES!! And you could see on the faces of Bon Acchord how impressed they were. Bravo! Digital Doug. Dynamics preserved, no overloading, no under-recording (which loses bit-resolution) and most wonderfully surprising, accurate tonality.

A party piece of Barry H at one past GM was to play the voice of Gordon Holt reading into twenty different professional microphones. And how different those microphones sounded. Which makes Doug’s result a real blast. And the December disk was just a prototype. Doug works on the digits at home, doing a frequency correction for the response deviations in his microphone. Then he ran off a CD for the fellows at Bon Acchord, which is a most polite thing to do and you can bet they’re thrilled by it. You want to hear how good? Then come along to the next GM and hear it thru top gear including the mighty Yamaha NS-1000 monitors.

Picky people say that MiniDisk can’t be any good. It’s a lossy medium. To get so much data onto a small disk, over 80% (yikes!) of the music is discarded “If something is happening loud, the soft bits below it are inaudible.” .Sure, and if you’d like to give me most of your money, you won’t notice any loss. DAT on the other hand keeps the whole lot, so it must sound far better, no? And a crummy cassette will be the ummm pits. Well blow me down, the psychoacousticians know a thing or two MiniDisk, DAT and a <good> cassette all sound in the same league. Not as good as Lucas or Barry or Jim’s venerable Revox G-36 valve tape recorders though. Ain’t technology wonderful.

Cards ain’t cards

Doug’s digital conversion takes place in his MiniDisk recorder. (aha! That’s where the religious experience happened.) Lucas uses a Sound Blaster Live! card, which some people whose ears I trust say is plenty good enough. However…though they’ve improved through the generations as sound processors, they’re not used by professionals for the ADC (Analogue to Digital Conversion) process.. If you want an argument, first go to Arny Kruger’s graphs at. www.pcavtech.com It’s his very audio-professional web site with technical reviews of over 50 PC sound cards. What stands out is differences in distortion, and in noise. Of course the noisiest place in the universe is inside a computer. Radio Frequency Interference is notoriously high, and to demonstrate it, listen to an AM radio as it approaches the nasty noise generator. How noisome is the noise? How long is a piece of interconnect? Obviating that can be done by having a stand-alone Analogue to Digital processor doing its job separated from the computer. That’s Honours stuff.

Burn baby, burn*

Writing (burning) one-off CDs is a common practise now among people with a computer nowadays, and isn’t that your grandmother? The commonest is to copy from one music CD to another-perhaps to make a compilation of one’s favourite tracks for in-car listening. The copyright police would look pretty silly gaoling you for that. Plenty more go to live rock concerts with a MiniDisk recorder and a microphone hidden under their coat, and get pretty knowledgeable about microphones. The third practise is to dub a favourite out-of-print vinyl LP to CD, once again for personal use only. This type is the trickiest, as it isn’t simply a digital-digital process, so interests we audiophiles. For ongoing tuition, one can follow the CD-R newsgroups discussions, from cdr@nt.navpoint.com.

Obviously then one should buy an $800 Philips CDR-870 or Panasonic all in one CD-writing box? Sorry, no, assembling your own computer-based audiophile system gives audibly better results. The guys on the Analogue Addicts # Internet discussion group have spoken. The technical word for those easy-peasy boxes is “crappy.” Oh, and they need to be fed blank CDs that have been pre-formatted for recording music on them. They cost more. You’re a pirate, so poor Michael Jackson must benefit.

Cheaper cards (the device that slots into a computer to do the digital conversion) add distortion and background noise. How intolerable it is of course depends on the rest of your system. Noise becomes troublesome with musos, who build up layers while composing on the keyboard to computer. How much worse are the cheap ones? Depends on who you ask, which is like how do you evaluate a movie review. You have to estimate the opinion / ears of the reviewer. “I can’t hear any difference between expensive gear and what I have, so it’s all a scam” is the universal cry of those with inferior equipment, we cognoscenti smirk ;-) . I do get the feeling that the sort of people who I’d trust, say it’s well worth spending a bit.

And the name that keeps coming up is not Creative Systems, the Sound Blaster people, but Turtle Beach. See www.voyestra.com & www.aventec.com They’re derived from pro sound, not from games & effects. Sound Blasters are there to add reverb and thunder and gunshots, and to have libraries of midi sounds like Mantovani’s string orchestra. My purpose was exactly as yours, to dub from LP to CD, and I came to the Turtle Beach Montego II card, which I got for $A170 locally, quite a lot less than the main Oz distributor (Moore Music) wanted, but more than the US price. However I became discouraged when two US companies couldn’t care about my order. Pity, as they were quoting $USfar less, + post. I got good help from somebody who knows sound, computers and service. and his price was W-A-Y below Moore Music, who have an expensive reputation in the musos trade. Graeme Spratling is the man, at Jet Stream Computing, 2 Wingrove St, Alphington, 9429.3779.

It will make an interesting Equipment experience, comparing it with say Doug T’s Sound Blaster, at some $100 less. Stir: Doug thinks digits is digits, but we know better don’t we? Hehehe.

One other point: SCSI is better. It’s a way of connecting computer components and it allows a more secure data stream to the written CD, with less risk of creating “coasters.” What proportion of them get wrecked thru data over-run? Not many really if you record at 2x. And SCSI costs more. Use Adaptek or Nero programs as editors, Cool Edit Pro to take out clicks and pops (else perfect noise forever) and watch out for the huge dynamic range of vinyl while recording. Those peaks will bite yer bum.

The FAQ (Frequently Asked Questions) by Andy McFadden at http://www.fadden.com tells ALL about writing CDs. And just for a start, not all CD-burners sound the same. Surprised?

Peter A

November 1999 Rockian Trading

At the November general meeting we again had the pleasure of Bev and Ian Hooper of Rockian presenting their latest CD’s with the support of local equipment manufacturers Redgum Electronics and Osborn Loudspeakers.

First up Ian treated us to a comparison between quality CDs and stereo sound from the Chesky Records 96kHz/24Bit DVD Superaudio disc releases.

Chesky Records have recently introduced the world’s first commercial releases of 96Khz/24Bit Superaudio DVD. Utilising the 24 Bit capability the DVD soundtrack, Chesky Records are releasing DVD discs that enable the listener to enjoy a superbly recorded 96Khz/24Bit stereo soundtrack which accurately conveys every little nuance of the performance. These recordings were originally recorded in the 96Khz/24Bit format and have been transferred to the DVD discs at the same superior standard.

Even with the difficult acoustics of the Willis Room to my ears the sound of these new discs was smooth and sweet with better sound staging and imaging than the normal 16 Bit versions.

We then heard a new re release from the popular Sheffield Labs Label and some of the latest recordings from labels like DMP, Dorian Recordings and Chesky Records.

Ian played a wide variety of discs including the following new releases as posted on the excellent Rockian Web page:

DORIAN RECORDINGS xCD-90277 - OF KNIGHTS AND CASTLES:- Burning River Brass.
DORIAN RECORDINGS DOR-90279 - THE MAD BUCKGOAT: Ancient Music of Ireland - The Baltimore Consort.
DORIAN RECORDINGS DOR-93186 - THE LITTLE BARLEY-CORNE: Winter Revels from the Renaissance - The Toronto Consort.
DORIAN RECORDINGS DOR-93190 - BALLADS OF THE SEPHARDIC JEWS - Sarband.
CHESKY RECORDS CD 190 - THE UNKNOWN PIAZZOLLA - Allison Brewster Franzetti, piano.
DORIAN RECORDINGS DOR-90272 - DANSE ROYALE: Music of the Baroque French Court and Theatre - Chatham Baroque.
DORIAN RECORDINGS DOR-90274 - THE VICTORY OF SANTIAGO: Voices of Renaissance Spain - The Concord Ensemble.
DORIAN RECORDINGS DOR-90275 - DOWN CAME AN ANGEL: Music for Christmas - Jacqueline Schwab, Piano.
DORIAN RECORDINGS DOR-93183 2CD set - J.S.BACH; CHRISTMAS ORATORIO - Bach Choir of Bethlehem, Bach Festival Orc., Greg Funfgeld
DORIAN RECORDINGS DOR-93187 - SHVEDOV: Liturgy of St. John Chrysostom - Slavyanka, Men’s Russian Chorus, Aleksei Shipovalnikov.
CHESKY RECORDS JD 186 TROPICANA NIGHTS - Paquito D’Rivera
DMP CD-526 & MAS CD-805 dts - SACRED FEAST - Gaudeamus, Paul Halley, Director.

While we do not have the space here to provide you with a review of all the discs we heard it is interesting to note that Chesky Records technical excellence is such that they have been honoured to receive a 1999 GRAMMY® AWARD nomination for Best Large Jazz Ensemble Performance for their release featuring Jon Faddis. REMEMBRANCES (JD166) (CHDVD176), recorded at St. Peter’s Episcopal Church in New York City, the recording is a collaboration between the acclaimed trumpet and flugel horn master Jon Faddis, and arranger, conductor, Carlos Franzetti. Franzetti also arranged and conducted the 39th GRAMMY® AWARD winning Portraits of Cuba (JD145), a Chesky Records CD featuring Paquito D’Rivera

The sound we heard from the Osborn / Redgum combination was in one word "big" as you would expect from these huge loudspeakers and power amplifiers. The bass was full and the sound clean deserving critical evaluation in a proper acoustic environment.

As usual, we will also had "Bev’s Bazaar" set up with plenty of members purchasing these high quality recordings throughout the evening.

Everyone had great time and we thank Bev and Ian from Rockian for supplying the fine music, and Greg Osborn and Ian Robinson for supplying their high quality speakers and amplifiers.

Ian M

October 1999 Whise Precision Audio

On Wednesday 20th October at the Willis we were treated to Graeme Huon’s presentation of the future of multi channel sound and some of the new technologies that Whise have developed to overcome the technical difficulties involved in delivering these new sound formats. Later in the evening we saw a rare video interview with famous Australian audio engineer Neville Theile.

As it turns out Whise have just returned from a whirl wind tour of the USA delivering their message to the THX market while riding on the leading edge of technical innovation in electro acoustic engineering and design.

Still hot on his heals from the USA trip Graeme delivered to us a well prepared, logical and concise presentation on a range of key topics covering the history of recorded sound, 5.1 multi channel sound and beyond, bass envelopment and concert spatialisation so as to illustrate how Whise fit into the big picture with their new PAM technology.

According to Whise we are in the midst of an on going 10 year product market life cycle where new ideas are first generated, the technologies to make it happen are then developed and finally consumer education and market take up. For this reason the idea of say THX and 5.1 has been around for a while (since the late 80’s) but most of us are only just getting around to buy it. As audiophiles and a key user group in this field we need to be not only aware and literate of the latest advances in audio but also mindful of the settling in time required for the industry music chain to get it right so as not to pass off the advances as gimmicks in the early stages.

Graeme went on to highlight the importance of bass envelopment and concert spatialisation which is terminology used to associate low frequency information and the effects of the acoustic environment with the listeners perception of where the sound is coming from in space. Without getting lost in endless audio techno jargon…. what this means is the more the listener is surrounded by an even array of sound sources the higher the level of realism in terms of recreating the original acoustic perceptions.

All this creates a reason for innovation and Whise have been busy partnering with key players in the multi channel sound industry such as the THM Corporation (for Tomlinson. M Holman) people to develop what is now known as WhiseTHM 10.2. If most of you are familiar with 5.1, that is three front full range speakers, two rear full range speakers and a dedicated (ELF) subwoofer, then the Whise THM 10.2 is the next step.

Effectively 10.2 extends the THX envelop to include the addition full range speakers for height so you now have upper and lower front left and right, centre and the same for the rear plus stereo subwoofers! Until recently technical limitations stopped the correct decoding and control of the various signal paths but Whise and the THM folks have come up the electronic black box to make it all work and recently conducted the Whise THM 10.2 demonstration in Las Vegas.

The feedback from those present at the demonstration fully substantiates the requirement for the addition speakers according to Graeme. This is good news for speaker and amp manufacturers like Whise, but I suspect bad if your running out of floor space like me or the WAF factor to consider.

Given the need for additional subwoofers and full range loudspeakers Whise have done some very thorough research into low frequency reproduction and have come up with new design tool dubbed Parametric Acoustic Modelling (PAM) which is a new milestone (developed by Graeme Huon and Greg Cambrell) along side the tried and proven Thiele-Small loudspeakers enclose design techniques. The benefits of PAM include 4 to 5 dB higher efficiency, lower distortion, precise control of frequency response, control of frequency response independent of group delay and the ability to make group delay very low according to Whise.

As PAM requires a very technical explanation as to its inner workings Graeme has indicated that he is more than happy to deliver a dedicated presentation for us on this topic some time in the new year.

To create low frequencies to THX specification requires enormous dynamic headroom and the Whise subwoofers incorporate a specially tooled heavy duty bass driver made by Melbourne loudspeaker manufacturer Loranz. Some of the specifications for these drivers include less than 1% low frequency distortion (normally about 10% for bass drivers), a 2 inch throw, a 600 watt voice coil and magnetic flux control rings on the pole piece.

We then heard a three way active loudspeaker from Whise incorporating PAM design modelling. Playing a variety of program material my impression was of one of solidarity and punch with zero overhang and an awe inspiring neutrality which makes them great for all kinds of music and of course THX. Running straight from a CD player some listeners may have been unnerved by the clarity and impact of these boxes which when compared to the accustomed warmth of the traditional valve sound could be interpreted as slightly clinical (but that is often the price for accuracy).

Even with the speakers atop one metre tables so as to get good projection down to the rear sets the bass went low and clean with plenty of muscle in reserve. Because these speakers incorporate their own amps, a total of three 60 watt units per box and an active crossover, there are no power losses as with passive networks, the crossovers between the drivers are smoother and in theory there is much lower intermodulation distortion.

Towards the end of the evening we settled down to view a video interview with famous Australian audio engineer Neville Thiele. In the interview Theile spoke with an insight, depth and perspective on the science of audio which made me realise that the work we had just witnessed of Graeme Huon and Greg Cambrell of Whise Precision Audio was in fact the next major milestone leading on from Theile’s original design techniques.

Our thanks to Graeme Huone and his team at Whise Precision Audio for a fascinating presentation of their technologies and products. We wish him well in his efforts to market these fine technologies to the multi channel sound industry.

By Ian M.

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September 1999 Redgum Audio

On Wednesday 15th September at the Willis Room we were treated to Ian Robinson’s presentation of Redgum Audio products. Ian is an inspired and accomplished speaker, and he provided a fascinating story of the evolution of his HiFi business and the development of Redgum amplifiers. He also demonstrated each of his products, proving to any doubting MAC members that Solid State - and in particular Mosfet - designs can be sonically excellent and full of energy.

He began by explaining that he had started out 25 years ago as a retailer, at various times had produced loudspeakers and only quite recently had moved solely into amp manufacture. Ian’s retail business started in Brighton, moving after a couple of years to Hawthorn, and the business spent a great deal of time on repair, seeing the whole range of amplifier problems from the seventies, eighties and nineties.

Ian warmed to the topic of amplifier design by explaining that he had seen many silly, avoidable mistakes in consumer hi-fi amplifiers over the years, and had mused long and hard over ‘a better mousetrap’. Realising that the mass production techniques of Japanese brands was almost impossible to best, he resolved that if he ever one day branched into amplifier manufacture he would be forced to compete not on price, but on quality and reliability.

In the early nineties, when the Redgum designs were prototyped, Ian spent considerable effort on the stability issues of conventional mosfet amplifiers and eventually hit on swapping the gate/source capacitors over from the N type devices to the P type. This was a serendipitous discovery, and flies in the face of convention, but works very well with all Redgum amps displaying high slew rates and unconditional stability - even into heavily capacitive loads.

Ian had been appalled with how easy it was to destroy the output stages of modern hi-fi amplifiers, and marvelled at the complexity of the protection circuits which were often ineffective anyway. He resolved to devise a better way, and after careful discussion with his transformer manufacturer was able to specify a transformer which delivered a limited, sustained current in the event of a short circuit which would not destroy the output devices. All Redgum amplifiers can withstand short circuited outputs at full power - a valuable feature too often ignored on much more expensive amplifiers.

The components

The Redgum RGCD2 is a high quality CD player featuring a uniquely serviceable and upgradeable replacement drive. This enables the transport, including the laser, to be replaced by a readily obtainable transport from a Personal Computer CD-ROM - at very low cost. The quality of the design automatically compensates any deficiencies in the transport with clever electronics, and according to Ian there are absolutely no penalties.

This is a novel approach to the manufacture of a HiFi CD player, but by way of confirmation the sonics of the complete system gave nothing away to ultra-expensive players.

Ian informed us that the Digital to Analogue Convertor (DAC) uses the high quality Burr-Brown PCM1710U Dual 20 bit Digital to Analogue chip with audiophile grade support components. This is configured for 8 times over-sampling, a digital filter, multilevel Delta-Sigma DAC, and an analogue low pass filter. The player achieves 92db THD+Noise and 98db Dynamic range with 110db signal to noise ratio. The digital circuitry was designed by Jon De Sensi of MusicLabs, another Melbourne company. Cabinet finish is solid redgum wood front panel, textured black steel chassis & cover. The audio output uses gold RCA connectors at the rear.

All Redgum amplifiers are visually distinctive with a redgum front panel, a lockable key switch (a useful feature for those who jealously guard their hi-fis!). An unusual feature is the dual mono volume controls using high quality, conductive plastic potentiometers.

The REDGUM RGi60 is a 60W x 2 integrated power amplifier/passive preamp capable of 60 + 60 Watt RMS into 8ohms continuous sine wave at the onset of clipping with less than 0.009% THD at all levels below clipping.

The Redgum 175w monoblocks include a passive preamp and produce a power Output of 175 + 175 Watt RMS into 8ohms continuous sine wave at the onset of clipping with less than 0.009% THD at all levels below clipping. This amplifier also uses a super quiet fan on its purpose-designed heatsink.

The Redgum RGS38I floor standing Loudspeaker features an attractive red gum wood veneer and a bass reflex, twin rear ported design. The 2-way, three driver system, employs a 25mm soft dome tweeter, and two 165mm polypropylene woofer/midranges with a combined frequency range of 28hz-20khz and a sensitivity of 94db/W/m, and a nominal impedance of 6 ohms. The crossover point is 2.8kHz woofer to tweeter and suggested amplifier power in the range 50 to 200Wrms. These speakers include BI-wiring as standard and five way gold binding post. The crossover uses polypropylene capacitors, air-cored inductors, wire wound resistors and a lead shot Chamber.

The Redgum equipment performed very well throughout the evening easily filling the Willis room with sound at high levels. At lower levels, which would be extremely loud for the average listening room, the equipment showed no hint of strain - a difficult feat in a revealing venue. At very high, almost deafening levels there were occasional hints of overload, but the amplifier was clearly working to maximum output and the overall performance must be judged excellent.

Initially Ian demonstrated a Chinese percussion sound track especially chosen for its ‘difficulty’. We were amazed with the authority and bass impact of the amplifiers and speakers, and wondered how such impact could be produced by such drivers of such modest dimension. At times light fittings could be heard resonating as the Willis Room approached low frequency saturation point. I was struck by the life which emanated from the speakers; this system had strong vigour. There was no sense of ‘flatness’, so common a problem with most Solid State systems I have heard.

A broad variety of program material was played throughout the evening, covering most of the musical genres. If asked to sum up the sound I would say that the amplifiers are very truthful, with perhaps a hint of dryness in the top end. The midrange is well balanced, and the bass astonishing. On very heavy passages, far above normal listening levels, there is almost imperceptible intermodulation, but this system is overall very detailed and clean. The immediacy or attack on steep wave forms was impressive while the amps maintained a sense of utter clarity on whatever we played indicating immense control and transparency. There was some depth in the sound stage - a credible achievement for a mosfet amplifier in my experience - but the real strength lay in the portrayal of instrumentation detail as though everything was close miked.

The overall impression was of outstanding value for money, and system versatility suitable for both hi-fi and home theatre, with the happy combination of detail and attack required for both.

Our thanks to Ian Robinson of Redgum Amplifiers for a fine demonstration, a fascinating talk, and an excellent opportunity to assess these fine Australian Audio products. We wish him well exporting these fine products.

Hugh D & Ian M.

August 1999 VASS ELS5 Electrostatic Loudspeakers

Charles Van Dongen of VASS Electronics returned again to the Willis Room on 18th August with his recently completed ELS5, a re-designed version of his 1998 model. The ELS5 retails for $3990 ($2990 to MAC members until mid-September), a considerable price reduction over previous models achieved largely through economies of labour. These are the second cheapest model VASS offer; the least expensive 1.5m model carries a RRP of $2990.

Charles recounted the tale of these speakers and their evolution, explaining the compromises involved and passing around a 4 micron roll of the Mylar film he uses to make the speaker diaphragms. Surprisingly, the Mylar film does not stretch, and great care is needed during assembly to tension it without tearing. Charles feels that this property of Mylar militates against a curvilinear panel since the movement of the film is greater in one direction than the other. This asymmetrical excursion leads to even order distortion, making the flat panel cleaner sonically. He proudly stated that recent refinements had conferred immunity to humidity, a vexing problem for most electrostatic speakers due to charge leakage. The 3dB corners for the ELS5 are at 50Hz and 20KHz. This is a remarkable achievement.

Electrostatic speakers require a step-up transformer to attract and repel the diaphragm with the necessary force to generate a sound wave — the high tension supply of the ELS5 operates at 2500 volts. This transformer has a turns ratio of 100:1, and requires major design expertise to avoid high frequency rolloff. By interleaving the primary and secondary windings and separating the primary into four sections and the secondary into five, Charles achieves a 3dB rolloff at 20KHz, a creditable figure for an iron-cored transformer of this type. It can be argued that this transformer is the single most difficult problem in the design of electrostatic loudspeakers, and Charles is to be congratulated for his progress in this area.

The ELS5 stands fully 2.2 metres tall, dwarfing even the tallest person. However, it is only 25 cms wide, so the footprint is quite manageable in even the smallest of rooms. It is beautifully finished on both sides with narrow Californian Oak panels running the full length, and an attractive black grill over the separate treble and bass panels, which are electrically common — that is, there is no crossover. Sensitivity is around 83dB/watt/1metre for 1KHz, and maximum sound pressure level (SPL) is 105dBA at 1m. This last figure is impressive for an electrostatic speaker and indicates considerable manufacturing refinement in the diaphragm tensioning and rigidity of the grid structures.

A proprietary conductive coating is sprayed on the Mylar. Charles revealed that the grids are 1.6mm thick steel, and feature full electrical protection in the event they are touched.

A sub-woofer is used to supplement frequencies below 200Hz. This comprises two side-firing 250mm Vifa woofers, mounted in a sealed triangular box of great rigidity. Each driver, of 4 ohm impedance, is driven separately by left and right channels. A sub-woofer is necessary because the excursion of an electrostatic diaphragm is not adequate for very low frequencies, particularly given the unbaffled nature of the rectangular panels and the limitations of the electrostatic forces driving the diaphragm. It certainly makes a big difference in operation, giving a full bass of admirable realism!

Driving the ELS5s was an ME 850 amplifier (RRP $5199), made by Peter Stein of Dyers Crossing in NSW, of 200 watt and 70 amp current dump capacity. Charles remarked that during testing he once measured a 30 amp speaker input at 15Khz. This phenomenon is a property of electrostatic loudspeakers; they require large amplifiers with massive current capacity, and huge, busbar-style speaker cables. In fact, these requirements narrow the choice of a suitable amplifier, and critics of electrostatic speakers stress this issue again and again — you can’t drive an ELS with a 300B Single Ended Triode. The preamp (line only) was the ME14 (RRP $1399), coupled with a Pioneer CD Player model 5705. This system was very quiet.

No speaker is more sensitive to room placement and configuration than the electrostatic. It requires low ceilings, generally no more than eight and a half feet (2.6m), and small room dimensions. Panel orientation is critical, and because of the planar propagation pattern will only project a proper stereo image into a small listening area. They are thus the speaker equivalent of a motorcycle; primarily a single seater application — and to some extent an acquired taste. The sound of the electrostatic has been described as "...a distant harp playing in heaven". The lack of a point source creates an ethereal, disembodied sound to an electrostatic loudspeaker which is an important experience for the audiophile. I noted the hallmark stereo image smack bang in the middle of my head. However, their efficiency is low, as are the absolute sound levels, and so a room filled with widely spaced, sound absorbent human beings is not an appropriate showcase.

Having said that, the VASS ELS5s perform remarkably well. The treatment of metallic instruments such as triangles, bells and xylophones is outstanding. The human voice, the acoustic guitar and the sound of clapping are very good indeed. The presentation of these sounds, and especially vocals, is the distinguishing sonic feature of electrostatic speakers and is well documented. Doubtless it is the reason they are still beloved by a select group of audiophiles all over the world — particularly in Britain, where the ESL63 Quad still reigns supreme after 36 years.

It is difficult to critique one component of a hi-fi system in isolation, particularly as the reactive nature of any electrostatic speaker makes it perhaps the most arduous load of all for an amplifier to drive. To make matters worse, I was unfamiliar with most of the recordings played, although I do know the Sibelius’ Karelia Suite well. I identified a number of deficient areas, but remain uncertain which component to blame. Aside from the vagaries of the Willis Room, legendary for its ruthlessness even with dynamic speakers, I have persistent doubts about the amplification. I believe that even the trojan ME, with it’s 70 amps of current delivery, is hard pressed to cope with the highly capacitive load of the panels presented via the transformer. It must be said that Charles demonstrated at high sound levels; much, much higher than would be necessary in a sedate living room, and in these circumstances I noticed the amplifier wilting audibly on several occasions, usually during heavy percussion.

I suspect that electrostatic loudspeakers are cruelly treated by conventional, push pull SS amplifiers because the clip characteristics of these devices is extremely audible. While electrostatics mandate the use of powerful, SS amplifiers, their transparency and drive requirements render clipping all too evident — a classic Catch 22. I believe more development of high voltage tube amplification with simpler, less compromised transformers of far lower step-up ratios is in order. A tube amplifier would largely solve the clipping issue because of the graceful overload characteristics and tolerance to reactive loads. This approach is quite practical, moreover, because it is presently used with electrostatic headphones.

My sole criticisms of the ELS5 thus relate to sounds of high intensity, such as percussion and vocals at the extremes. I heard several brief, ugly episodes of clipping — particularly during several percussive passages, male vocals and a number of orchestral pieces. A soprano rendition of Mahler’s Songs of the Wayfarer carried a strange, grainy bloom at the upper registers when pressed. A Rockabilly Blues number with powerful percussion sounded bloated and bassy, swallowing the male vocal performance at times. However, on quiet passages, when suitably seated, and particularly with soft vocals and orchestral backing, the detail, grace and refinement was entrancing.

I would like to hear the ELS5/ME850 once again in a small room, on material selected for known quality and content. I would expect better control of percussion, more controlled stereo imaging through optimal positioning, and impeccable treatment of voices — all characteristics I heard on Wednesday night, but which were sadly masked by the stresses of The Willis Room, a large and unflattering venue. I consider tube amplification almost mandatory in this role, preferably with a direct drive step-up transformer loading the plates of the output stage. I believe the vast majority of us suffer audio memories so flawed that the only satisfactory assessment of loudspeakers is comparative, and I suggest the best test is to compare the ELS5 with the benchmark ESL63. I understand such a test will be performed as an A/B test at Chris Mogford’s on Wednesday 25th, and await further judgments. My only regret is that a work commitment in Canberra prevents me attending.

I enjoyed listening to these fine loudspeakers, but am disappointed that the conditions at the venue did not permit a fair assessment. However, as an engineering achievement, the VASS ELS5 is impressive, and all the traditional hallmarks of the electrostatic loudspeaker are clearly audible. At any price, and they are inexpensive, these are fine loudspeakers; but great care must be taken when selecting an operating environment and an amplifier to drive them.

Addendum

After the listening test at Chris M.’s on 25th August, Chris and Gary M. were able to give me their impressions. Here they are, in edited form:

Chris:

ESL shootout:

Firstly I wish to thank Charles for taking the time and energy on that cold night.

The first impression that I’m sure everyone felt was the different bass between the two. Quad employ special techniques here and so may not be fair to compare.

Also I have the quads crossed over at 150Hz (24dB/oct) most of the time anyway. I very rarely switch them to full range (one simple knob switch).

The ESL5s were certainly big but there was still some mutterings that my 8’4’’ ceilings were too tall compared to the 7’3" ESL5s. I don’t believe that the height should have been a problem. In my room I felt that his subwoofer was not good enough and I think Charles recognizes that. If I had more room I would have connected my own subs, I think they would have performed much better.

Anyway, to the real story: I noticed a not unpleasant reflection from the rear wall that I had never heard before; even with the rear wall padding. Obviously due to the height of the ESL5s. I found their mid to top end to be very clinical compared to the ESL63s more rounded sound. Both still had that wonderful electrostatic transparency. Not having golden ears I’m afraid that’s the best I can do. I believe that the ESL5s in the right room would sound great coupled to a good sub. Perhaps their height is the problem. We have to remember that they are in the cheapest range and I believe represent great value. I can’t wait to start having a look at his new centre channel speaker he’s designing at what could be a fair price. For those well heeled there’s always the ESL1 or 2.

Gary:

The sound of the ELS5 was fat, bloated, and pounding with the bass wound up to such a level as to mask many of the fine qualities. I found this difficult to accept; bass is not a separate entity, containing huge quantities of inner detail. Simply turning it up does not achieve a satisfactory result. Everything else has to suffer when this approach is taken.

But… Things really took a turn for the better when the sub was removed. Detail, air and space appeared; individual instruments and voices could be analysed and appreciated. Delicacy and insight abounded. Certainly, the tonality and dynamics were a touch compromised due to the missing low mid/upper bass suck-out but the extreme bottom was very good - better than I was prepared for.

I do not believe that repositioning the loudspeakers accounted for the general improvements outlined in the paragraph above. Contrary to the maker’s claim I also believe that similar results would have been evident in the Willis Room. A better way of filling in that 8db of hollow rather than overriding everything with that huge bass lift should be found.

Now to the Quads. Taken on their own: damn good. Probably on "classical" the upper bass would not be missed but with material that derives much of its character from bass string and fingerboard noises I think too much is lost. I found the midrange to be very strong. This made a meal of vocals - to the detriment of overall balance. Treble presence and detail were good, but took a step back from the vocals.

The Quads are probably fabulous for orchestral middle strings, solo vocalists or instruments.

In their current states and without also having an alternative pair of speakers - I couldn’t live with either of them. I did however find that Charlie’s "Angels" (with bass bin removed) showed up a serious flaw in the Quad sound. By comparison the Quads sounded very "phasey". This is probably only something one would notice with the very quick A-B feature being used.

If I am correct, this phase inversion (full or partial) would go some of the way to explaining the depth apparent in all the music played on the Quads and the relative ease of positioning them. The design compromise arrived at in design and manufacture means that they are never right and conversely never wrong! With the VASS you either have it or you don’t but it is always sweet and clean.

And so I thought the VASS’s to be tonally superior!

Tony O’Callaghan commented that the ELS5 highlighted sibilance. This is probably so, although I thought they added an edge/distortion to the top end and when the music grew busy, quick and loud it was a rather blurred. I believe that the tall panel configuration stretches the sound out too much, giving an unnatural sound. I would prefer a shorter, wider layout.

MAC would like to thank Charlie very much for his time and effort in presenting his speakers to the Club, both at our GM and at Chris’ home. This is the third time Charlie has ventured to ask us to comment on his speakers, and I hope that he accepts the comments in the spirit in which they are given, that of constructive criticism.

Hugh D.

July 1999 A DVD versus CD Show Down

The aim of the July presentation was to draw some comparison between the equipment alternatives currently available for playing normal 16 bit CD (and 24/96) software and to provide members the opportunity to discover some of the differences in the sound qualities of the various hardware combinations.

The equipment:

We had 3 digital sources; the Kenwood DVF 9010 DVD player kindly supplied by Nick Karayanis from Audiophile, Peter H's trusty (12 year old) NEC CD player, the Seldon Stokes diy DAC built by Alf L., and a Camelot Dragon Pro 2 De Jitter Device supplied by Kendrick P. ~ our new Equipment convenor.

Other equipment used in the comparisons were the Kendrick P's MUSE Model 3 Preamp and Parasound HCA-2003 Power amp and the VIVACE SE loudspeakers again, kindly supplied by Audiophile.

The discs and tracks played were:

Rob Wasserman - Duos
MCA 42131

Angel Eyes with Cheryl Bentyne (She is one of Manhatten Transfer)
Badi Assad - Rhythms
Chesky jd137
A gandala das andas (Dont ask for a translation)

Jennifer Warnes - Hunter
Private Music 01005-82089-2
Way down deep

Ports of Call - Eiji Oue and Minnesota Orchestra
Reference Recordings (Prof Johnson 24 bit recording)
Finlandia

The events were essentially but not necessarily in the order outlined below, as we went back and forth a few times and had to set levels a few times as well. Due to a technical oversight we were unable to make use of Peter's NEC CD player with the external decoder as planned as it did not have a digital output.

Also, in the initial stages the due attention was paid to getting the sound levels equal for each comparison. This was much appreciated as a number of members were unable-able to come to conclusions if the levels are out of whack, although many people in the Club can compensate for level differences somehow.

I should also point out that the comparisons were for the main part not done using "on-the-fly" switching as we did not have duplicate copies of the CDs or a suitable switching box (Perhaps the diy group could come up with something!)

However this type of comparison was used with the 16 bit CD versus 96/24 DVD hardware and software test with some interesting outcomes. Many listeners were unable to make a clear comparison between the two in the first of several listening rounds.

I understand that many people seem not to like this "methode-compari", preferring to get the emotion from one listening sample, then play the whole sample again on another set up.

To this end we played a few minutes of particular tracks then replayed the same as quickly as possible through the alternative hardware under comparison.

On the amusing side, who noticed the "monkey-chatter" leaking through the PA system in the hall? This was very disconcerting indeed. It sounded a bit like a local radio station getting into the PA equipment. Anyway, if you didn't hear this, you are in bliss, although can you trust your judgements if you missed it?

In keeping with the format of the meeting I have included a number of the comments from members pertaining to each comparison.

1. Peter H. NEC CD player versus the Kenwood DVF 9010 DVD.

In this comparison we played a short excerpt of a standard 16 bit CD through the NEC CD player and then played the same tracks with the Kenwood player. The levels were matched as close as possible in each case. Feedback from the audience included the following comments:

"The NEC CD player presented string plucks with too much flesh and not enough string. Bowed notes sounded very harsh and grainy again with little body of the instrument or timbre coming through. The NEC missed much of the smaller micro detail in the background also (I always listen for this - and value it highly - often you get the best sense of the recording venue and ambience from this)."

"The Kenwood wasn't perfect, but was easily the best of the bunch. Strings sounded like strings. There was still some hollowness in the midband. Micro detail however was better and stereo imaging as good as any on the night. Perhaps it was a little polite overall and maybe rolled at the extremes, but not as much as the tube DAC did."

Others however thought "There was very little difference between the CD player and DAC in this comparison!"

2. The Kenwood DVD player versus Kenwood DVD with Sheldon Stokes valve output DAC.

In this comparison we played a short excerpt of a standard 16bit CD through the Kenwood and then played the same tracks with the Kenwood with the digital output of the DVD player feeding the Sheldon Stokes DAC. Again the levels were matched as closely as possible. Feedback from the audience included the following comments:

One member commented "The tube based DAC had a lovely sweet midrange, but compromised both frequency extremes noticeably. It was also felt timing and the leading edge of the notes lacked that vs the DVD DAC or NEC machine for that matter. Was disappointed given the high cost and content in the machine. Perhaps different tube implementation/type may assist?"

While some other members commented that "The midrange on the Sheldon Stokes tubed DAC was superior, and the top end a little sweeter. But the bass was mushy and indistinct."

3. The Kenwood DVD player with Sheldon Stokes DAC versus Kenwood DVD player with Sheldon Stokes DAC and Camelot Pro 2 De Jitter device.

In this comparison we played a short excerpt of a standard 16bit CD through the Kenwood feeding the Sheldon Stokes DAC and then played the same tracks with the digital output of the DVD player feeding the Camelot Pro 2 De Jitter device which then supplied the Sheldon Stokes DAC with a digital signal. Again the levels were matched as closely as possible. This was probably the most subtle of all the comparisons and was difficult or most members to consistently identify. Feedback from the audience included the following comments:

"Essentially the Camelot Dragon Pro 2 added something and took something away."

Interestingly one member commented ~ "Ashamed to say I couldn't pick the difference." Very, very close - for me at least."

While another member commented. "Sometimes I like the smoothness of the de-jitterer and sometimes I prefer more aggression.". The de jitter gave the impression of more depth and better timing on some recordings or was this the subtle effect of a change in frequency response and missing high frequency information."

4. The NEC CD player with 16 bit recording versus Kenwood DVD player with 24/96
recording.

In this comparison we played a short excerpt of a standard 16bit CD through the NEC and then played the same track using 24/96 DVD disc in Kenwood in 24/96 mode. In both cases the analogue outputs of each player feed directly to the Muse Model 3pre amp without any additional processing. Again the levels were matched as closely as possible. Feedback from the audience included the following comments:

"The DVD was a noticeable improvement, but for double the cost of the discs and the investment in the player some would doubt the value, especially if they had a reasonable player already." (Whilst my position was non ideal, I was amazed others could not discern which was the DVD in the demos (50% wrong!)). Livingston Taylor's song at the end was inspirational however and most likely, widely enjoyed."

Another member felt "Chiefly ambience and 'air' but difficult to pick in the Willis Room In a smaller room, maybe rather more contrasting. Maybe there's a lesson there."

One interesting point was made that if you have an older CD player and are thinking about DVD, you could well consider a combined CD/DVD player of similar calibre. Later on, add a discrete DAC and dejitter for 2ch if you need.

Ultimately this type of equipment comparison requires a lot more rigorous listening and quantifying of results before any really meaningful judgements can be made. And lets not forget that it also depends a lot on the type music you play and the other associated components in your system.

In conclusion I think we all had a great time and we would like to thank all the participants for their commitment and support of this presentation.

We would especially like to thank Audiophile for the supplying the Kenwood DVF9010 DVD player and the VIVACE SE speakers ~ making this presentation possible. They performed extremely well, and provided a level of fidelity seldom heard in such a challenging acoustic environment. In a normal listen room they would of course sound even more impressive. I would recommend any member of the club looking for a DVD player or new speakers contact Audiophile for an evaluation of these models.. Audiophile can be found at 519 Brunswick Street, Fitzroy North. Ph. 9489 4864.

June 1999 AGM plus more

President Matt Takes Over

Club Subs Unchanged

Bedini’s CD Clarifier Trialled

The new President of the Melbourne Audio Club, Matt Jelicich, took over at last month's successful Annual General Meeting. Most other club positions were filled, and an active club year seems assured.

Outgoing President Peter H. briefly reviewed the past club year. There had been a small but real increase in membership, and the general level of activity within the club remained high. It was particularly pleasing that the Pop and Acoustic music groups were once more functioning actively.

The Treasurer's report showed that on a total turnover of about $5,000, the club came out with a small surplus of $247. As the coming year is expected to incur only a modest increase in costs (the Willis Room hire fees are expected to rise slightly), the AGM approved the recommendation of the Treasurer that membership fees should remain unchanged.

That means that all memberships are now up for renewal at $50 for the standard rate, and $40 for pensioners, full time students and persons who live more than 50 km from the Melbourne GPO.

After the AGM business had been concluded, President Matt's Bedini CD Clarifier was trialled in a double blind testing arrangement. A high quality CD playing system had been assembled, using Hugh Dean's Glass Harmony monoblock amps, Peter H's NEC 903 CD player, a purpose built pre-amp by Lewis Muratori, and the large monitor speakers recently built by Lewis Muratori. These high efficiency (97 dB/watt/metre approx) units use 380 mm (that's 15 inches) Audax bass drivers, and Focal midrange and treble units. With a large room divider set up to hide conspirators Matt Jelicich and Peter H., two copies of several CDs were smuggled into the no-go zone behind the screen. Of each pair of CDs, one was treated with the CD Clarifier, the other left untreated.

"Treating" involved mounting the CD on a small spindle on the CD Clarifier. When the unit is switched on the CD is spun slowly and some sort of fluctuating magnetic field is applied.

Bev and Ian Hooper at Rockian Trading had kindly loaned us pairs of several new release CDs from their stables, and the other CDs had been borrowed from members. In the event, five tracks were used. They were -

1. Dorian CD 90266 - "Cha-Cha Lounge" featuring a group called Proteus 7. We used the track "Peanut Vendor"

2. Mercury 442 541 2 - "You Are There". We chose the Detroit Symphony Orchestra conducted by Paul Paray playing "Marche Joyeuse" by Chabrier.

3. Red House Records RHR CD 98 - "Slant 6 Mind" featuring Greg Brown. We used the track "Billy from the Hills".

4. Chesky JD 183 - "Ephemera", featuring Carla Lother. We played the title track.

5. From a CD made by Doug Tipping from some of the recordings he has made at concerts around Melbourne, we heard Cantata by Strozzi, performed by a soprano, cellist and harpsichordist.

The operator-conspirators were supplied with an appropriate check sheet on which they recorded which CD was "treated" in each case, and which of them was played at each part of the trials. Audience members received a different check sheet on which they recorded their observations.

For each chosen track, the first test consisted of a playing of one of the CDs (called "A"), then the other CD ("B"). Listeners were asked to record whether they thought they could hear a difference between A and B, and if so, which they thought sounded "better".

36 audience members furnished replies, mostly from members who clearly concentrated intently and made genuine efforts to give the device a fair trial. A small number in the audience were convinced at the outset that it was all a hoax and took the listening trials casually. One even grew agitated enough to storm off declaiming that it was all an insult to his intelligence!

From the 36 responses, we received 163 total replies to the first test on the five tracks used. (i.e. there were a few abstentions). Of these 163, a total of 130, that is 79.8%, thought they could hear a difference between "A" and "B". Not quite so many could nominate which of the two they preferred. Comparing listener preferences with the information as to which of "A" or "B" had been treated, it transpires that 64.0% of the preferences listed were for the treated CD.

To summarise this, a participating 36 people listened to five separate tracks (off 5 different CDs). They knew that one time they were listening to a CD treated with the Bedini, and the other time to an untreated CD, but did not know which was which. Close to 80% thought they could detect a sonic difference, and about 64% of the time they preferred the treated CD. Anyone with shares in the Bedini Clarifier company might be feeling pretty happy at this stage.

For Test 2, we tried something more demanding. The conspirator-operators were told to play us the chosen track twice, either both times from the same disc (and it could be both times treated disc or both times untreated disc), or once from the treated and once from the untreated disc. Of course they had to record what they had played each time. The audience, meanwhile, had to try to assess whether they had heard the same or different discs in that pair of playings. We repeated this three times for each chosen track, so that there were 15 trials in Test 2.

Now it was not a question of whether the audience members thought they could hear a difference. This was a test of whether they really could or not. For each response sheet, I scored, not whether it was a treated or untreated disc, but whether the listener was correct or incorrect in their assessment of "same" or "different". Note that some people "missed" a turn occasionally. Maybe their attention had been distracted. "Unsure" was an allowed response. Further, as always at a General Meeting, some of the audience went home at the supper break, so that the two tracks tried after supper had a smaller audience.

A total of 413 separate responses were recorded during Test 2. Of these only 186, that is 45.0%, correctly judged whether they had heard the same or different discs. 55% of the responses were wrong! On the face of it, the Bedini Clarifier isn't going too well now. Looking more closely into the results, it is interesting to note that where the real situation was that the "same" disc was played twice, 38.4% of the responses were correct, but where different discs were played we got 51.4% correct responses. (The operators in fact swapped it around. That is for Track 1, they played same, different different; Track 2, different, different, same; Track 3, different, same, same, and so on). Is this significant? Were our audience better able to discern when there were different discs than same discs? Or were we just more inclined to opt for "different"?

One other possible factor was the nature of the discs themselves. The member who owned the Bedini unit that we borrowed for the night believes from his own experiences at home that the thing works most effectively on well used CDs. That is, the more often a CD has been played, the more do you notice an improvement when you "Bedini" it. If this were right, it would be as though repeated playings gradually build up some residual something (magnetism?) that the Bedini removes. In our tests, Tracks 2 and 3 were on well used CDs borrowed from members, tracks 1 and 4 from new CDs supplied by Rockian Trading, and number 5, Doug’s CDs, had been played a few times.

OK, so then we look to see whether the two well used CD trials (Marche Joyeuse and Greg Brown) scored any better than the others. The answer is that, yes they did fare a little better. In the reponses to the Greg Brown CDs, 51.1% of the responses as to "same" or "different" were correct, and for Marche Joyeuse, 48.1% were correct. (Compare the overall 45.0% correct total).

Another issue is location of the listener in the room. If I was organising a trial like this again, I would have a place on each response sheet for the listener to record somehow where they were in the room. For instance, my experience in the Willis Room is that only a very few seats, maybe the 3 middle seats in each row, have any chance of picking up stereo imaging. I had taken the trouble to pin the response sheets together in fives, so that all of the responses from any one audience member were kept together. It was certainly true that some individual respondents got a high number of "correct" scores, although no one got a 100% correct score on Test 2. From the data I have therefore, I cannot say whether those in prime listening positions did better.

To give my interpretations of these results, these trials provide no evidence to support the claim that the Bedini CD Clarifier improves the sound of CDs. Those members who came to the trials firmly believing the thing to be a confidence trick are entitled to adhere to their view until someone produces evidence to the contrary that these trials could not produce. To any member who was thinking of buying one, my advice would be don't. Not for the present, at any rate.

To those members, including those who already own one, who believe it does work, I would suggest you need to do some further trials. It usually helps to have some sort of theory as to how a thing is supposed to work when trying to design a further series of experiments. A possible theory might go like this - There are electric currents and magnetic fields inside CD players. It might be possible for repeated playings of a CD to lead to some sort of residual magnetism building up on the CD. (This fits with the contention, as yet unproven, that the Clarifier is most benefit on a well used CD). Within the CD player, some components may operate by the application of magnetic forces. One such, I believe, is the system for moving the lens which focuses the laser beam and does the tracking, which employs a magnet and small coil. Too much residual magnetism on then disc is then assumed to introduce errors in the operation of that part of the CD player, with resultant deterioration of the sound. The problem in all this, of course, is how could a CD get magnetised - being composed of polywhatsit plastic and aluminium (usually). There is the paint used on the non-encoded side to print the brand name of the CD and other information. Are there any magnetic compounds (blue cobalt compounds? red or brown iron ones?) used in inks that are used to print on to CDs? If so, then the CD demagnetiser would be expected to be useful after the CD has been played a certain number of times, but the treatment would have to be repeated again and again over the life of the CD.

If anyone is hell-bent on buying a Bedini , I suggest you should first seek the co-operation of either President Matt, or ex-President Peter (they are both obliging gentlemen). Go to their home, armed with one or two pairs of identical CDs which have both been played plenty of times. Come to think of it, you might need a few CD pairs, if my magnetic inks theory has any validity. Then, using just yourself alone as the audience, sitting in the prime stereo position, go through a series of blind trials like the ones we did at the GM. If you can tell the difference between treated and untreated discs under these conditions, you can buy with confidence. And, of course, let the MAN Editor know quick smart.

(I am sure the Bedini owners group will be sharpening their pencils for their letters in reply. Ed.)

by Kevin M.

May 1999 Three suave systems from Encels

Encel Stereo returned to the Melbourne Audio Club scene in May with three systems based upon those superbly crafted little bombshells from Italy, the Sonus-Faber speakers.

David Galloway, manager of the Richmond store, selected one "high-end aspirational" system which costs about $23,500 all up, a " high-level musical" system costing $11,700, and a "good quality entry level" system which sells for about $3,700.

The top system featured the latest Rotel RCD 991 HDCD CD player, an Alchemist APD21 pre amplifier with Alchemist APD 20 150 watt per channel power amplifier, and Sonus Faber Guarneri Homage speakers. The CD player in this system uses low-jitter digital circuitry which includes dual 20-bit Burr-Brown PCM63 D/A converters and Pacific Microsonics PMD 100 digital filters. There is a user-selectable dither control, and balanced or unbalanced outputs.

The Alchemist "Forseti" pre-and power amps from Britain are striking looking, high specification devices. With unusual shapes, and highly polished metal finish they had some members swooning in ecstasy, and others muttering about poor taste. You pays your money and you makes your choice. And the $23,500 Sonus Faber Guarneri Homage speakers are absolutely the last word in elegant craftsmanship. The cabinets are crafted from multiple blocks of natural timber precisely shaped and glued together to give superb rigidity, and polished to bring up an absolutely glorious finish. Tiny things, mind you, in 12 litre reflex cabinets. These are designed and built in a part of the world where it is assumed that everyone lives in flats or tiny houses, and loudspeakers need therefore to be first and foremost small. They have two drivers, a 150 mm bass/midrange driver and a 28 mm silk dome tweeter. These speakers come integral with a pair of hefty 124 kg stands which are elegant looking things in their own right.

The middle system started with a Rega Planet CD player. Encels have recently taken on distributorship of the Rega range of products, and the Planet has been acclaimed in reviews overseas. The amplifier used in this system was the Sonus Faber Musica, a 50 watt per channel (into 8 ohms) solid state amplifier featuring dual JFET differential input and error corrected MOSFET output stages. Finally the speakers were the Sonus Faber Signum. These are even smaller than the Guarneri Homage, having 8 litre cabinets, a 150 mm mid/bass driver and a 20 mm silk dome tweeter. A brochure supplied on the night tells us that the cabinets of the Signums are built from "staves of armonic walnut wood" with "internal tuning of lead". Does this mean the cabinets are partly lead lined ? Very solid Sonus Faber speaker stands were used, built from timber and iron, and with hollow upright members which are filled with either lead or sand, similar in concept to our own club stands.

The entry level system had a Rotel RCD 951 HDCD CD player, a Rotel RA971 60 watt per channel integrated amp, and a pair of Sonus Faber Concertino speakers. The CD player sells for about $750 featuring high end componentry such as Roederstein resistors and Black Gate capacitors. The Concertino speakers are like the other used in this demonstration, are two-way jobs, in 10 litre cabinets which are built from solid timber and leather.

David Galloway played the same four tracks over each of the systems. One was The Entry of the Queen of Sheba, from Handel's "Solomon", Kiri te Kanawa singing "Pastorelle" from Canteloube's Songs of the Auvergne, a track from Keb' Mo' on HDCD, and a track from the sound track of the movie Leaving Las Vegas.

The top system sounded to me to be silky smooth, with excellent imaging and a rather warm frequency balance. That gave the voice reproduction from the soprano track a clear sweet sound utterly free from any hissy sibilance. Overall, the sound was powerful and very transparent. Warmth and smoothness were the major impressions I got. If there were any things lacking, not surprisingly very deep bass would be one, but I also felt that there was some lack of high frequency detail about cymbals, snare drums and even the piano tone.

The middle system sounded very crisp and clean too, but with the frequency balance pushed more towards the treble. This gave the sound more sparkle in areas where I thought the top system might have lacked a bit, but also made the female singer's sibilants a deal more "spiky". Violins sounded not as silky smooth, but there was more "resin" about the sound. Imaging and transparency excellent as before.

In the lowest cost system, there was good general reproduction, but some of the precise spatial information was now lost. In the orchestral track, there was more like a "block" of sound than the separate sound sources clearly discernible before. When you looked at the price, however, this was very acceptable sound indeed. There was plenty of grunt and presence, and the extra sibilance heard was less offensive than many systems you hear.

After supper we heard music selected by our music group convenors, and whilst we tried to compare the sonic differences between the individual speakers or the individual amps, time did not allow me to form many conclusions. Of the three systems as presented, the top system had a suaveness about it that was unassailable. It was just so-o-o-oh smooth. Yet the extra treble detail of the middle system attracted me, and I am not sure that I would not choose it in an overall shoot-out. At least, if I was considering buying the Guarneri speakers, I would want to hear it with other amps.

As a bonus we heard one track from a CD recorded by our own Doug Tipping in his role as an honorary recording engineer for 3MBS. We heard Men of Harlech sung by the Victorian Welsh Male Choir, with the Hawthorn City Band. Doug recorded this at a performance in the Robert Blackwood Hall at Monash University at a concert in February. Doug used here one of his home-made coincident microphone systems. The recording was originally made for 3MBS, but when the people associated with the choir heard it they arranged to have it produced as a CD for sale to choir members and supporters.

This was one more highly professional meeting from the people at Encels. Everything was prepared and presented properly, reliably and smoothly. A most enjoyable meeting, and the club thanks David Galloway and his helpers.

April 1999 Delicacy and detail from Whatmough's P.30

Top model in Whatmough's Performance Series of loudspeakers, the "P.30" took centre stage at our April General Meeting, and gave a very convincing account of itself.

Designer and proprietor, Colin Whatmough, explained that he nows markets three ranges of speakers. The most basic are the Classic Series, ranging from $695 to $1495 in price, then comes the Performance Series from $1295 to $2595, and at the top the Signature Series comprising the famous 202 Leadline priced at about $3,000 and the 502 I at about $9,000.

A number of surround sound models are also available, plus two high quality sub-woofers. The Tempest is a subwoofer using a 250 mm polypropylene driver, with built in 100 watt bass amplifier giving bass extension down to a – 3dB point at 24 Hz. It costs $1295. In use at the meeting with the P.30 was the other subbie, named the Typhoon, which uses the same built-in amp, but a 250 mm woven carbon fibre cone in a slightly larger enclosure, and sells for $1995.

The main speakers, the P.30s, are a 2-way design, which sell for $2595 per pair. The tweeter is a 30 mm inverted dome Ti-oxide unit from Focal, and equally spaced above and below that are a pair of Audax 170 mm bass-midrange drivers. Claimed efficiency is 91 dB for an input level of 2.83 volts (1 watt at 8 ohms), and the – 3 dB point is claimed to be 40Hz. Colin believes, however, that proper matching with a good sub-woofer like the Typhoon offers a more open and natural sound-stage. Although very few musical instruments emit notes below 40 Hz, ( a big bass drum and an organ among them), there are very low frequency components in the various ambient sounds that can contribute greatly to a feeling of "presence". He argues that it is desirable to cut the sub-woofer out of play at all frequencies above the low-point of the main speakers. If you do not, there is likely to be a difference in "speed" in the region where the two systems operate together that results in blurred and masked sound.

For the demonstrations, Colin used an 80-watt per channel solid state Myryad amp (about $2200), and the same company's CD player ($2500).

Colin went on to present a wide ranging selection of musical items. First up was a jazz quartet (piano, guitar, bass and drums) on a CD titled Dukes' Big Four. The cymbals were especially crisp and natural, and the little group came across clean as a whistle. Then from an HDCD sampler disc by Reference Recordings called "Tutti" came a large orchestral piece – Rimsky-Korsakov's Dance of the Tumblers, played by the Minnesota Orchestra. Reproducing this sort of thing is a much more complex task than the previous item, of course, and whilst there was a good impression of orchestral size and power, I felt it sounded a bit "fat", by which I mean light on treble sparkle.

Next a favourite demo disc of Colin's, on Vanguard, the 1963 "Reunion at Carnegie Hall" concert by The Weavers. We heard "Guantanamera". Great "presence" in the sound, yet a total lack of harshness. The on-stage noises such as foot-tapping were improved markedly by the use of the sub-woofer.

And so it went on. James Newton-Howard and Friends on Sheffield Lab, a Mozart Horn Concerto on EMI played by Barry Tuckwell and the Academy of St Martin-in-the-Fields, Harry Belafonte at Carnegie Hall on RCA. This latter recording came over with great presence and detail. I liked the natural and un-exaggerated sibilance. Paris Texas, with Ry Cooder, then Pink Floyd with Just Another Brick in the Wall. Then that Dorian recording of Mussorgsky's masterpiece for solo piano, Pictures at an Exhibition, arranged (some would say, de-ranged) for organ. We heard an excerpt representing a fantastic ballet of chickens which are still in their shells, but played this way on a huge organ it sounds like a dance of a herd of wheezing, asthmatic elephants. Not the fault of the speakers, of course!

We heard a track from a 1987 Warner Bros CD called "Shaka Zulu", performed by Ladysmith – Black Mambazo. Vividly reproduced vocals and percussion and clapping and foot-stamping. Colin turned off the sub-woofer and re-played this track. There was a loss in sonic "depth" to the stamping and other percussive sounds, but the main speakers alone did a very good job for all that. Indeed, I liked the extra cleanness of the sound, and ended up not being sure that I preferred the subbie on after all.

Hyperion Knight played piano (Chopin), and great transparency from the CD version of a 1975 Pablo recording Basie Jam, with Count Basie on piano and trumpet, two saxophones, trombone, guitar, bass and drums. Great transient reproduction and good transparency.

In summary, I thought that these speakers performed superbly, giving loads of delicacy and detail in a neutral, natural way. For $2,595, they are amazing. There was ample power and ease in the sound, and the sub-woofer certainly added "authority" to the sound. Anyone in the market for speakers at this sort of price should surely go to the Whatmough factory and give the P.30s a good hearing. Mind you, it would be interesting to lend an ear to the 202 Leadlines in the same sitting, just to see what an extra $400 would do.

As to Colin's demonstration, this, like many others I have heard from the same source, was simply a model of how to demonstrate audio equipment.

March 1999 25 years of the Melbourne Audio Club

by Kevin M

The Willis Room was jumpin' on March 17th. Jumpin' to sounds that exemplified 25 years of Melbourne Audio Club's service to this city's audiophiles. Jumpin' to a hall full to capacity, and then some. (Over 90 people joined in.) And jumpin' to the joys of meeting up with loads of former members, some of whom we hadn't seen for many years.

Two guest speakers had been chosen for this very special meeting, two people who, more than anyone else, had been responsible for getting the Melbourne Audio Club established in the first place. They were Michael Phillips, at the time of the Club's formation in 1974, a head salesperson at Encel Stereo, and the proprietor of Encel Stereo, Mr Alex Encel.

In his well prepared and documented talk, Michael Phillips cast back over his own lifetime in music and audio, looking at the events which may have influenced his crucial actions in early 1974. Michael spent his childhood in NSW, some little way out of Sydney. He picked up an interest in music from his parents, and an interest in audio from magazines like The Gramophone. Having commenced working in Sydney, Michael had read advertisements by what seemed a most enterprising Melbourne hi-fi retailer, offering to mail audio gear to any address in Australia. When he stumbled across the fact that Encel's were in the process of setting up a store in Sydney, Michael was off like a flash to sniff around. Pretty soon the people at Encel Sydney offered him a job as a salesman, and Michael was hooked. Michael's love of good sound reproduction grew along with his love of music. When he read in the magazines of overseas "Gramophone Societies", he wondered if such a thing could work in Australia. Some of the reports of British G.S.'s seemed a bit on the stuffy side, but, …., he still wondered.

In due course, a fellow named Vince Ross was transferred to take Michael's job at Sydney Encel, and Michael was transferred to the main shop in Bridge Road, Richmond. (Vince later returned to Melbourne, and was an inaugural member of the club. A year or two later he moved to Perth and set up his own hi-fi store there, and established the Western Australian Audio Society).

The US firm Hartley introduced their 10 inch full-range drivers, and Encels started importing them. Encels built appropriate cabinets for the Hartleys, and ran some evening demonstrations at the shop. At one such evening demo, a few people were chatting over coffee. There was Michael Phillips, full of enthusiasm, and Dorothy Bristow (now deceased, but the original Vice President of the club), George (now deceased) and Jenny Truskin and Graham Bath (still a club member, lives up country). A comment was passed along the lines "Wouldn't it be great if there was a club in Melbourne that did this all the time ….", and Michael decided that the time was now. He dropped a sentence into one of the weekly Stereo Topics ads that Encels ran in The Age Green Guide pondering the interest in an audio club for Melbourne, and received so many phone calls that he approached Mr Encel. Could we sponsor a meeting to test interest in an audio club? Alex agreed, and the next Stereo Topics invited those who might be interested in forming an audio club in Melbourne to meet at 8.00 pm on such and such a night at the Encel shop. Those of us who read and responded to that invitation recall the excitement of that preliminary meeting. The number who came could scarcely get into the shop, and it was agreed that a club would be formed, and a few pro-tem officers were appointed, Alex Encel President and Dorothy Bristow Vice President, to get the thing going with a view to proper election of office bearers in a few months time. In that first two or three months, as the original membership lists were being compiled, Michael Phillips and those around him established the basic club structure that remains intact today. There would be monthly "general" meetings in some venue large enough to accommodate everyone in the club who wanted to attend, and then lots of other meetings in members' homes or hi-fi business premises, or anywhere appropriate, to pursue sectional interests within the club. It was decided to elect a convenor for each of these special interests, to make sure that activities were arranged on a regular basis for that particular interest. In the event, more than half the "group convenors" turned out to be elected to pursue some kind of music.

And so it was that the club from the very outset was set up to cater for both the technical and scientific interests of professional audio people and amateur DIY dabblers, as well for those whose interests were primarily in the music.

Michael had prepared his talk in depth. He brought along his own audio system, very much a 1999 system. Michael interspersed his talk at crucial points with brief excerpts from quality recordings which had been significant to him at various stages in his audio odyssey.

Next up Alex Encel spoke briefly to the meeting, pleased and proud that the club he had helped to inaugurate so lone ago had proved sufficiently valuable to have endured so long.

Alex recalled that the audio world of 1974 was considerably different from that of later years. In 1974, an interest in high quality sound reproduction was the preserve of a freakish "in group". They were frequently the butt of the jokes of "normal" people. He could recall cartoons at the time that stereo was introduced showing long-haired, odd-looking types perched on one another's shoulders to hear the stereo effect. Women frequently hated hi-fi. In the showroom, wives could be seen tugging their husbands away from the salesmen, seeking to steer them towards a furniture shop where we could get something "decent" in a nice polished cabinet.

Soon after 1974, as the large Japanese firms came into hi-fi in a big way, hi-fi burgeoned and the general public gradually became convinced. Alex reminded us that the wheel has continued to turn, and that we are now closer to the 1974 situation than to the 1980s one. The broad mass of people have lost interest in hi-fi. People are working longer hours and have less time to listen to music at home. They go out to dinner more. Home computers take up spare time. And, to cap all that, home theatre is now available at costs low enough to interest the general public.

Yet the dedicated audiophile remains, and Alex sees an indefinite future for people like thew members of our club – those who are simply passionate about their interest in music and good sound.

For the rest of the program, we heard music. There was music that was current in 1974, tracks that were making a splash in 1974, and there was music of 1999. In all there were four sound systems used throughout the night – two representative of "good" sound 1974, and two right up to date in 1999.

The "today" system used by Michael Phillips comprised solid state Breta amplifiers designed and built by Laurie Cohen, with Audiostat speakers by Michael Brown a NSW speaker guru who has used French Triangle drivers in spherical "cabinets" cast in concrete.

For the 1999 system we have to thank Nick K of Audiophile. This comprised a Carey valve line stage pre-amp (using 6SN7 valves), which retails at $1249, and is available to Club members for $999. The power amp was a Carey push-pull power amp based on 2A3 output tubes (about 16 watts/channel) and which sells at $4800 with RCA valves ($3800 to MAC members until the end of March). The CD player was a belt drive CEC, and a pair of Amber "Vivace" speakers, 2-way but with an additional rear-facing "ambience" tweeter, locally built from European drivers.

The first of the 1974 systems comprised a Dual 1214 integrated turntable and arm, fitted with a Stanton 681 E moving magnet cartridge (provided by Jim Menadue), the Club's own Radford solid state amplifier and a pair of Spendor BC1 speakers, courtesy of Peter A.

For a second system representative of the days when the club began, we had a Thorens TD 125 electronically controlled turntable, with Grace G840 arm, and an Onlife 20B cartridge. "Onlife" was fore-runner to the Dynavector brand, and this cartridge was a high-output moving coil which just preceded the great boom on moving coils which was set off by the Supex SD 900 , Denon 103 and the like. Speakers were KEF Concerto kit speakers, a three-way bass reflex design using KEF's old B139, B110 and T 27 drivers. All the above were kindly provided by George Elliston. For amplification, we had SAE Mk 30 pre-amp and the SAE 31B power amp, solid state amps from the middle 1970s, thanks to Graham Cobb.

Michael Phillips' selections included –

    L'Arlesienne Suite (Bizet) – Detroit Symphony Orch, cond. Paul Paray (Mercury)
    Take Five (from "Time Out") – Dave Brubeck Quartet.
    Mad Sene (from Lucia di Lammermoor) (Donnizetti) – Maria Callas
    You're So Vain – Carly Simon
    Siegfried's Funeral Music (Wagner) – Vienna Philharmonic, cond Georg Solti.
    Symphony No 1 (Sibelius) – Vienna Philharmonic, cond. Lorin Maazel
    The Look of Love – Dusty Springfield
    Private Investigator – Dire Straits
    Pictures at an Exhibition (Mussorgsky) – Pogolerich, piano.
    Dessay – Natalie Desai.

From the Carey system loaned by Audiophile, we heard –

    Baby Please Don't Go (from the CD "Spectrum Plays the Blues") (Volcano Records)
    Country Gardens (from "Percy Grainger in a Nutshell") – City of Birmingham S.O., conducted by Simon Rattle.
    Duke Ellington, with Joe Pass, Ray Brown and Louis Bellson (Pablo)
    Slant 6 Mind (from the CD of the same title) – Greg Brown (Red House Records)

On the two 1974 systems, we heard tracks which we found from early editions of the Club Newsletter were creating interest –

    Violin Concerto (Beethoven) – Henryk Szeryng violin, Concertgebouw Orchestra Amsterdam, cond. Bernard Haitink (Philips)
    Seven Come Eleven (from the album "Hello Herbie") – Oscar Peterson, piano (MPS)
    White Rabbit (from the album of the same name)-- George Benson (CPI)

It has to be said that the two modern systems gave forth the better sound. They were cleaner, crisper and better controlled. Both the antique systems were to some extent woolly in the bass, and there were plenty of other imperfections. Whilst clearly this was not a situation in which any sort of comparisons between systems was possible or intended, at least we all went home content that the last 25 years in audio hadn't been entirely wasted.

Michael Phillips' system with the concrete spheres performed very well indeed. The was an abundance of clean, crisp sound with excellent resolution of detail. It was powerful sound, ample to project out into this room with 90 or more people present. Michael Brown acted as CD jockey, and at times he drove things pretty hard, occasionally a bit too hard for comfort perhaps.

The Carey based system from Audiophile also gave excellent resolution and detail, and on some of the tracks heard, there was a very nice feeling of space and ambience. It was another of those cases where the sounds we heard seemed far ahead of what the claimed power output might have led us to expect.

At around 10.30 the formal part of the show ceased, and we moved to the lush foyer area outside the Willis Room. We had extended our booking time from the usual 11 pm to midnight, to allow plenty of time for supper. President Peter and his team had set up a supper of wine and cheese, supplemented by a delivery of dozens of fresh cooked pizzas, so that we had plenty to chew over while we chewed over old audio times and the present outlook.

It was a great meeting. In a way, it's a relief to have the first 25 years behind us. Now we can go about getting on with the next twenty five.

February 1999 DIY rides again

Ian M and the DIY members of the club returned by popular demand to present the February General Meeting, and the aim was to get into some of the DIY demos that had missed out last December.

First up was Matt Js by now notorious modified Leak Stereo 60. (For a discussion of the modifications to this amp, readers are referred to the February 1999 edition of MAN, page 4 et seq.) The amp was being fed from a Marantz CD 63 SE CD player, and was being heard through Hugh Dean's large partial horn enclosures each containing one Fostex 208 driver.

We listened to Joan Byez in Concert, performing What Have They Done to the Rain?, Dire Straits from their album Love Over Gold, and Greg Brown on his 1997 CD entitled singing Maria. Finally the last movement of a Sonata for Cello and Piano by Brahms, on a Naxos CD.

To my ears the music on all these tracks came through as relaxed and pleasant, but it was not all that lifelike. I missed a degree of detail and sparkle in the highest frequencies, and felt that there was some woolliness in the lower frequencies. In the Brahms Sonata, the sound was overall rather scrappier than in the other tracks.

At club home meetings I often hear it said that such-and-such CD "only cost $n at JB" (where n is some small number, often under 10). As regular attenders to these meetings know, I will sometimes express some reservations about this seeming worship of the cheap CD. It seems to me that if, say, Naxos CDs are cheaper than anyone else's, either they are running at or close to a loss and will soon go out of business, or the other companies are raking in exorbitant profits, or else the cheap label people are cutting corners somewhere. Well, we know that Naxos make a practice of recording little known artists, presumably thus minimising artists' fees. I'll accept the argument that a performance by a superstar like Karajan or Solti will not necessarily be good, but will retaliate by arguing that being a nobody also doesn't guarantee a good performance. Indeed I would reckon that there is a clearly higher probability of getting a good performance out of experienced and highly regarded performers. And if a company is focused on cutting costs, they are just as likely to cut corners on technical quality as anywhere else. If a cheap product turns out to be of superior quality, that's something to celebrate, but we are not going to promote the highest quality in the products we can buy if we place too much store by seeking cheapies.

At one stage the CD player was taken off the concrete paving slab which had been there hitherto, and placed on a lightly inflated small diameter bike tube. I do believe that this did clean up the sound somewhat. Sweeter mids and trebles especially.

Next up was Hugh D's Lifeforce amp, a solid state push-pull amp which includes in its circuitry a 12 AU 7 valve incorporated in some mystical, secret way. Same CD player and speakers as before. We heard the same tracks that had been played on the Leak, and the sound balance was totally different. With the Lifeforce, the sound was much leaner, with higher frequency harmonics all much more prominent. This gave more sparkle to guitar, piano, cymbals and things, but much less rich weightiness to, say, the tone of the cello. I could prefer either amp depending on the material being listened to. Thus Greg Brown's guitar accompaniment carried much more treble detail in a drier acoustic with the Lifeforce, but his vocals sounded croakier, harder.

Over to a system provided by Alf Lepp. He had a commercial valve pre-amp by Contan of Melbourne (now out of business), and Alf's own DIY Nelson Pass design 20 watt single ended Class A solid state power amp. Alf used a Rotel CD transport with a DIY DAC which uses valve output stages. We first heard Alf's system through the Hugh Dean speakers that had been in use earlier, and then through some speakers built by Lewis Muratori. These are based on a single Fostex 207 driver per cabinet, with what Lewis described as "compression" loading. The cabinets, considerably smaller than those in Hugh Dean's, are built from 25 mm MDF.

Listening to Sibelius' Finlandia, for example, the Muratori speakers gave a more transparent sound with a more detailed sound stage. Low frequencies were still very firm and rich. We stayed on the Muratoris for a while. Sarah Kaye on Chesky was singing Spanish Harlem. The vocal sounded very believable, smooth and detailed. This was the most transparent sound heard so far in the program.

Then we got to Holly Cole, singing Take Me Home You Silly Boy. This time, the green LEDs inside the CD case were turned on for a while, then off for a while, and so on. Some in the audience thought the volume level increased a bit with the LEDs on (the amp controls had not been altered). Others thought the voice was cleaner and clearer with the LEDs on, and others said there was more of the low level detail audible with the LEDs on. In all honesty, I could detect none of this.

The DIY people would do well to pursue this green LEDs business a bit further in some of the home meetings, where there is more time for detailed analysis of the sound. If it is right that flooding the inside of some CD player boxes with green light improves the sound, what's our theory? Someone in the audience opined that it would be to do with green and red being complementary colours. (Complementary colours, in the additive colours sense, mean two colours that when combined give white light. Actually I think green and magenta are complementary, as are red and cyan. But what would complementary colours be doing?) I guess the right thing to do is to first establish whether green light in the CD player really is improving the sound, and leave the theorising to later.

Another good meeting. Plenty to just sit back and enjoy. But also plenty to challenge us. Good work, fellows.

January 1999 Tweaks and minor upgrades

We all dream of squeezing a drop or two more performance at negligible cost from our existing audio gear, and five members made presentations to suggest how we might proceed.

Danny B started the ball rolling. He outlined the upgrading of an amp can proceed by describing his work on the Leak Stereo 60 which had been discussed at the December DIY General Meeting. The Leak Stereo 60 began production in 1962, and was a 30 watt per channel push-pull amplifier using EL 34 output valves. Other components used were carbon composition resistors, paper-in-oil signal capacitors, electrolytic power supply capacitors and long lengths of tin-plated copper wire.

Resistors. Due to age and the high ambient temperatures in valve amps, most of the resistors in this amp were measuring at least 20% above their nominal values. Of the modern replacements available, metal film resistors are accurate, cleaner and "faster" sounding, but Danny considers that the sound they produce is not consonant with the relaxed, warm sound of this amp. Wire-wound resistors can be used to great advantage, but only in some locations in an amp (trial and error here?). In this sort of amp, Danny preferred to stick with carbon resistors, choosing Japanese high quality 2-watt high stability types. They are less noisy and less prone to drifting in value than those being replaced.

Capacitors. Paper and oil capacitors can have the greatest impact of any single passive component in an amplifier. But they can degrade seriously with age. Any ingress of water into the metal cases will be absorbed by the paper, and it is thought that modest impurities in the paper itself can lead to degradation too. The upshot eventually is DC leakage as the resistance of the dielectric is lowered. Plastic film capacitors are much more stable, and Danny replaced all the paper-in-oil caps in this amp with Axon tin foil with polypropylene film 630 volt caps. These are available from the WAR people in Western Australia. Electrolytic capacitors are not long-lasting devices, and are prone to drying out and failure with aging. Danny recommends systematic replacement of electrolytics with new ones every 5 years or so as a matter of course.

Connecting Wire. Like so many high quality amps, the Leaks were built to look pretty inside. Components were arranged neatly on a generously sized tag board, and all wiring was bundled neatly and tied down to look just so. Unfortunately this sort of wiring maximises mutual inductances and capacitative effects between the conductors, some of which are carrying 400 volts, while others have minute, low-level signals. It might not look so pretty, but it is sonically much better to open up the cabling bundles, and to connect up the components "point-to-point" with the shortest possible pieces of cable, avoiding parallel cabling as far as possible.

Pentodes Connected as Triodes. Thousands of Leak Stereo 50 and Stereo 60 amps all over the world have been modified by converting the EL 34 output pentodes to triode operation. This is done by cutting out the action of the screen grids by connecting them, via a half-watt 100 ohm resistor, to the plate (anode). The tube now has a more linear loadline, lower plate resistance, reduced gain and higher transconductance. The amp now has lower gain, and a corresponding reduction in feedback. Those who like that sort of thing argue that the triode operation gives less harsh and more "relaxed" listening. The downside is that, as feedback is reduced, so intermodulation and total harmonic distortion are both increased. About 4% at 15 watts! Danny argues that despite this, the amp in this form recovers from clipping much more rapidly than in its original form, so can still be expected to sound good.

Lucas C was next to present some thoughts on tweaking. Lucas' reaction to Danny's talk was to recall trials done a few years back by the then DIY group on sonic differences between components. Most found at that time that changing resistors made more difference than changing capacitors (Yes, but did they try paper and oil caps?). The poorest sounds were thought to be from cheap, everyday metal film types (thin sounds), the carbon resistors they tried were considered better. Holco metal films were liked, and best of all were wire wound resistors.

Green Lights in CD Players. One way that has been found to improve the sounds from many CD players has been to bathe the interior of the machine in green light. You can use say a dozen small green LEDs (eg from Dick Smith ) and wire them to a suitable simple power supply. Place them in the CD case clear of other components, fixed perhaps with Blue Tack or dobs of silicone sealant, to shine green light right around on the spinning disc. What is all this about green and CD players? Green pens, green light. We need to ghet to the bottom of it surely. (a) Does it happen, or is it imagination? (b) If it happens, why green? Someone suggested that the laser light by which a CD is read is red, and green is remote from red in the spectrum. Maybe. But blue is more remote. And ultra-violet more so. Anyone prepared to set up an ultra violet emitter in their CD player? (c) If blue and/or ultra violet improved things too (more?) what is going on here?

Inexpensive Speaker Spikes. Builders' hardware stores sell "dowel centres", small rods with a metal cone on the end to aid accurate drilling of holes for dowelling. A box of four or five for about $3. The cones make perfectly satisfactory speaker spikes. Get the largest of the sizes available.

RF Interference. RF interference can come down the power lines (and is an increasing problem). Requires some sort of power conditioner to fix. There is a whole can of worms to be sorted through to find power conditioners that clean up the supply without loss of dynamic capability. Or RF can come as radiation through the air. Shielded power cables are strongly recommended.

Hugh D. Hugh discussed the vexed question of harmonic distortion measurements. I suppose his central point was that percentage distortions of the individual harmonics are the only measurements worth talking about. A single note emitted by almost any musical instrument comprises a fundamental frequency, which is the lowest frequency component and the part that determines what note it is (i.e. the pitch), on which are superimposed a number of higher frequencies (harmonics). The timbre of the sound we hear is determined by the precise detail of this mix of frequencies. If a trumpet (say) and a piano play the same note, it is usually easy to tell by ear which is which. Different harmonic contents to the two sounds are a major way our ears can tell a trumpet note from a piano note, although there are other clues (in this case, different ways the notes start up and decay). When the harmonics present in an original sound are added to or decreased, we are talking about harmonic distortion. Added harmonics are objectionable to a listener roughly in proportion to the square of the degree of the harmonic.

Push-pull solid state amplifiers which operate in Class B normally have outputs which are relatively rich in odd-harmonic distortions (3rd, 5th, 7th harmonics). These are the more objectionable harmonic distortions, and usually emanate from the output stages themselves. A good feedback system will get theses distortions down to acceptable levels. If we go to Class A operation, where the transistors don't turn off, we have large amounts of heat generated which must be dissipated, but the odd order harmonic distortions are naturally much lower, and the sound accordingly much more acceptable. The best topology for reducing odd number harmonic distortions is to go single-ended. You pay for this with horrendously low efficiency.

Those who use valve amps are well aware that different makes, even different batches by the same maker, of the same type of valve can sound quite different. But even the connecting wire inside an amp can influence the sound. There are numerous tales of dissimilar metals in contact (eg silver coated copper) being one cause of sound degradation. Hugh speculated on the possibility of some diodic action between the copper and the coating. In the ensuing audience discussion the question of the directionality of hook-up wires was raised. There was the usual split between "How could it?" and "But it does". "It couldn't make any difference", said one faction in the audience, "music signals are alternating, so they travel in both directions". "Ah yes", someone responded, "but markedly asymmetrical alternating signals". Hugh suggests trying the wiring both ways and see if there you can detect a difference.

Hugh also discussed the use of PCB boards. For best sound, keep the copper tracks as short as possible, as thick as possible, and take good care to make all corners of the tracks smooth and curved (avoid sharp corners).

John D was next. He started off in pessimistic mood. Audio systems are hopeless; they can't compare with live music. What he was getting at was the idea that you need to develop some sort of reference against which to judge your sound system, and this is best done by listening to plenty of live music.

John was adamant that interconnects do make a significant difference to the sound of a system. He has been trying his hand at some home made interconnects of similar style to the well-known Goetz connectors. He bought copper sheeting of appropriate size, and cut narrow (1 cm wide) strips for the two signal paths using scissors. He wished to separate the two flat copper strips with teflon, and found that you can purchase open teflon tubing of suitable dimension to simply slip the copper inside. But the price of the teflon was $32 per metre, so he backed off that idea and simply wound teflon plumber's tape around each copper strip. Use teflon gas-pipe tape, not water-pipe tape, which is thinner.

John expressed doubts about the value of using speaker spikes unless the floor beneath is very solid, e.g. concrete slab. He cannot see the value if on a whippy wooden floor. This brought about a spirited discussion in which various people supported or denigrated spikes on every conceivable sort of floor. I couldn't find any conclusion here.

When changing a component and comparing the sound, John argues against rapid A/B comparisons. Better to take a good listen to sound of the system before the change, make the change and leave the system settle. For days or weeks. Listen frequently, and in due course, change back to the first condition and listen for some time.

Jim M started out with some advice about capacitors. He advised getting rid of all electrolytic coupling capacitors. He likes polypropylene caps. Mains suppression caps, signified by the letters MKP on them, are rated for 250 volts and are metallized polypropylene. Jim doesn't like paper-in-oil caps as they suffer from time smear distortion.

Jim has read of some experiments carried out with speaker cables which came up with a conclusion that you should look for low resistance and low inductance in speaker cables. Appropriate winding can produce the desired low inductance, but you may pay for this by incurring high capacitance. The trick is to see then whether the particular amp being used can handle that sort of capacitance. A very good inexpensive speaker cable can be made from a good big coaxial cable, type RG-213/U. This was designed for uses such as carrying signals to transmitters, and is obtainable at around $1.78 per metre from Cables Plus in South Melbourne. You can use the Inner core for the live wire, and the shield for the return of your speaker cable.

In general it is best to avoid feeding RF signals into amplifiers, and the use of well shielded interconnects is indicated. If desired, a double layer of shield is a good idea. Earth one-ended shields at the higher power end (i.e. an interconnect from a CD player to a pre-amp has its shield earthed at the pre-amp. Likewise one from a pre-amp to a power amp, earth the shield at the power amp end.

There was lots of discussion from all around the audience on all these points, and many members expressed their appreciation of the efforts of all the panel members. We'll do it again some time.