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July 2017 Avantgarde Acoustic Zero TA XD

June 2017 AGM + The Camel Audio Action Project

In my more impecunious years, I twice dabbled with designing and making my own loudspeakers - and the results of both attempts were a bit dire. In hindsight, how could I possibly expect to reproduce what KEF or B&W could achieve with their 50+ years of experience and million-pound research budgets with the items I had at hand: a pair of cheap 6.5" polypropylene woofers with pressed-steel frames and some 1" plastic-dome tweeters from Jaycar for the first trial, and a pair of paper-cone Super 8/RS/DD wide-range drive units from Wharfedale, dating from the late 1960s, for the second? This particular model from Wharfedale has been called 'one of the most crummy drivers ever made' and 'probably the worst driver I have ever had': see http:// www.troelsgravesen.dk/WharfedaleSuper8.htm. Clearly, I was not off to a good start with this attempt. My burr-walnut veneered boxes were, however, superb. It was thus with some trepidation that I approached last month's monthly meeting, but the equipment showcased on the night provided an unusual and very, very pleasant surprise.

Ron Newbound, immediate past convener of the Audio Action group, demonstrated the DIY troupe's most recent effort: The Camel (named for obvious reasons). Ron started the night's discussion with a declaration of the two questions a loudspeaker-designer has to answer at the very beginning of the exercise. First, is the primary consideration what the speaker looks like, what it sounds like, or what it costs? Ron indicated that, as an audiophile, the answer is what it sounds like. Then comes the issue of cost, which had to be reasonable. Then, last but by no means least, might come aesthetics. Second, how to load the bass driver? This is not nearly as simple to address as the first question. The Audio Action group (10 original members, plus an eleventh coming in at a later date, each contributing $100 to the venture), took the brave decision to develop a transmission line, one of a multitude of ways loudspeaker designers have devised to deal with the problem of the energy emitted from the rear side of a speaker cone. As Ron pointed out in his introduction, it is also one of the most clever, devious, intriguing and potentially frustrating ways.

The fundamental problem is that when a speaker cone vibrates, it generates sound from the front and from the back. If the frequency is high, the wavelength is short and the two sources do not meet and cancel out. But if the frequency is low, the wavelength is inevitably long (f = 1/.) and the output from the back does meet the output from the front, and the cancellation means the end of any really deep low-frequency response. One way of dealing with the problem is to mount the speaker on a flat but infinite baffle, one that extends an infinite distance away in each direction from the driver. This would certainly stop the front and rear waves from meeting and cancelling, but with an obvious practical limitation for the average person's listening room. Another way is not to deal with it all and have the loudspeaker operate as a baffleless dipole; this is the approach used (necessarily) by most electrostatics and even by some cone-speakers, including some really high-end designs from Jamo and, in Melbourne, with Kyron Audio's spectacular Kronos for a mere $120,000. Peter Comeau wrote a beaut article on this type of design in an issue of Hi-Fi World in 2008 (see http://www.hi-fiworld.co.uk/ loudspeakers/68-technology/144-designing-loudspeakers-open-baffles-andbass- part-15.html).

A third option is to place the speakers in a sealed box, so the rearward energy can't go anywhere. The box is then stuffed with material to absorb the energy coming from the back of the cone. This is in many ways a modification of the infinite baffle, the supposedly infinite baffle merely being bent so that it totally encases the drive unit. But sealed-box designs can be resonant and to sound obviously boxy, sometimes even plummy. And the energy generated out the back of the speaker cone is inevitably lost, so they are inefficient. A really clever modification is to use the air trapped in the box as a suspension mechanism to control the excursion of the speaker cone - enter here the 'acoustic suspension' design pioneered in the 1950s in the USA by Edgar Villchur (and his wife Rosemary, who often gets little acknowledgement for her role in it all) and Henry Kloss. This led to the suite of loudspeakers made by Acoustic Research and, later, by KLH, both exceptionally popular in their time, and for good reason. Page 34 of The Absolute Sound's Illustrated History of High-end Audio. Volume 1. Loudspeakers has a touching photograph of Villchur and friends comparing the sound of a live string quartet with the sound of his new AR-3 loudspeakers, under a massive oak tree in some idyllic spot, presumably in Massachusetts. Low efficiency was a problem when they were used with valve amplifiers, but the introduction of solid-state amplifiers using bipolar transistors in the 1960s rendered it largely a non-issue.

Before all this though, some bright spark had the idea of using, rather than trying to dissipate or destroy, the rearwards energy. If this energy coming out the back of the speaker could be diverted so that it came out in time with that emanating from the front of the cone, the two would reinforce and, magically, you would have not only solved the rear-emission problem but got a louder bass response for nothing. The problem was that the mathematics for optimising the sizes of the box and the port (length and diameter and shape) so that they worked collaboratively with a particular bass driver were a real mess, and applications were almost totally an empirical processes of trial and (much) error. Then, in the 1960s and 1970, A. Neville Thiele and Richard Small worked out the mathematical parameters to place the whole approach on a firm theoretical footing. Many people forget that this work was done in Australia: Thiele was employed by the ABC and Small was at the University of Sydney. It was largely ignored because it was originally published in an Australian electronics journal and American and English loudspeaker designers, being parochial, missed it completely. After all, what other than meat pies and drum-braked Holden cars could ever come from Down Under? Certainly the complex mathematics that were needed to solve this particular problem; they could come only from the BBC in London or from Massachusetts or California. The general consensus is that bass-reflex loudspeakers have deeper but slower bass that sealed cabinets, and that they are more choosy about their placement in a room (especially if the port faces rearward). But their manifest advantages - increased efficiency and a lower bass cut-off - meant that a large proportion of the loudspeakers made commercially today follow the T-S bass-reflex design.

An alternative approach to using the rearwards energy is to horn-load the drivers. Paul Klipsch is the man here. Not only is the rearwards energy put to good use, but the horn more efficiently couples the otherwise appallingly mismatched impedance of the (comparatively very heavy) bass cone with the vanishingly light mass of air it is supposed to drive. Horn-loaded bass speakers are therefore phenomenally efficient (up to 20%, compared with the less than 1% for most other designs) and so can be driven by an amplifier of only a few watts. Ergo the re-emergence of the single-ended triode brigade. Conversely, if you are of the Grateful Dead or Lead Zeppelin or Deep Purple persuasion, amplifiers with a couple of thousand watts output could be used to generate sound levels of truly stratospheric, possibly lethal, dimensions.

Horn loudspeakers then have staggering high efficiency and beautifully low distortion. But against this is the tendency for them to squawk and to colour the sound, not to mention that a horn that effectively couples a bass driver to reproduce usefully low frequencies is truly gigantic, often occupying an entire room, even when folded. And this is the reason they are most often used for midrange and tweeter loudspeakers - but the clear exception of the fullrange applications favoured by, for example, Lowther in England. And they can work fabulously: witness Gerald's system in Hampton.

Now, finally, onto transmission-line loudspeakers. In this design the pressure wave coming from the back of the bass driver is directed into a long tube lined with absorbent material and progressively dissipated. In theory the line has to be infinitely long, but in practice can be folded internally and made into more manageable proportions. The design very neatly gets rid of the unwanted rearward energy and does away with most of the undesirable resonances that plague sealed-box designs. An elegant modification is to make the end of the line open, rather than to terminate it in a blind end. This has some similarity with the bass-reflex approach outlined earlier. The end-result is a design with an open, spacious bass response that goes far below that of a typical loudspeaker, sometimes even below 20 Hz.

The earliest practical application of using a transmission line design is likely to be the Stromberg-Carlson radios of the 1930s. The approach got a thorough theoretical treatment by Arthur Bailey of the Bradford Institute of Technology in England in 1965, and the most obvious recent producer of transmission line loudspeakers has been IMF in England, which after a legal blue with Irving ("Bud") Fried, their American collaborator, morphed into IMF Electronics Ltd. They made a comprehensive array of transmission line loudspeakers, then in turn morphed into TDL (Transducer Developments Limited) which continued the work, albeit ultimately with a less ambitious portfolio of products, and then into TDL Electronics. I have a pair TDL Electronics loudspeakers from the early 1980s which I use daily in my office (they are currently in use, conveying something soulful from Muscle Shoals). TDL Electronics seems to have gone the way of the Dodo, but in its place the Professional Monitor Company in England continues the noble tradition of transmission-line designs. Only a few weeks ago I heard a pair of PMC Fact.8s while I was auditioning a pair of floor-standing Sonus Fabers, and very nice they were too (at $15,000 or so).

So this is the background to The Camel, the latest creature produced in the mythical laboratories of the Audio Action group. This thing is no mere botch -up job using a couple of cheap 6.5" woofers and an anonymous 1" plastic dome tweeter plonked in a MDF box, with a 5.F capacitor serving as a crossover. No - not only is it a full-blown 3-way transmission line design, but it uses novel type of tweeter. I had originally thought the tweeter was a cut-price copy of the famous Heil Air Motion Transformer (AMT). But Red MacKay pointed out that this was likely not the case, and Ron subsequently confirmed that my diagnosis was wrong too. According to Ron, The Camel's tweeter has a planar diaphragm and it is not pleated like a real Heil AMT. The 'voice coil' runs up and down the Kapton membrane and the north and south pole of the magnetic field are in front of and behind the diaphragm. He described it as an 'Air Motion Transformer planar tweeter'. It isn't a standard ribbon tweeter, as they have magnetic poles on either side of the ribbon, not to the front and back of the diaphragm. Anyway, the creature that Ron and the team used was of Chinese origin, and cost a mere $25 each.

The other two drive units in The Camel have a better pedigree: both are from Peerless, a 7" aluminium-cone woofer and a visually matching 5" aluminium -cone midrange. The crossover is a complex device, with a gradual 1st-order series design used for the bass and midrange units and a steeper, 3rd-order design for the switch to the tweeter. Crossover frequencies are 220 Hz and 3,000 Hz, respectively; not only is this a pretty standard type of frequency pairing for a three-way loudspeaker, but the Chinese device cannot go below 3,500 Hz or so. Other tweaking with the crossover removed the higher frequency resonances of the bass and midrange drivers. Ron said the efficiency was around 89-90 db per watt, and the impedance is as flat and uniform at 6 ohms as he could get. These two characteristics are, I think, really important, for reasons I'll describe later.

Although aesthetics were not the highest priority on Ron's list, they could not be ignored and the final product was really quite attractive. The front panel is a surfboard-shaped slab of laminated European beech, and the transmission line is cleverly contained with a cylindrical outer cylinder (300 mm diameter, 6 mm wall thickness) fabricated from a concrete form-work mould, painted a matt black. Inside it is a 200-mm diameter, 3-mm thick cardboard packaging tube, and it forms the inner extension of the transmission line. The bass unit is mounted two-thirds the way along the outer tube:

Ron pointed out how precise this positioning had to be, as a vertical variation of even 1 cm along the line had a measurable impact on bass the response. The top is externally flat, but internally a hemisphere (made out of expanding foam) to reflect the bass pressure wave sound down the smaller tube. It is ported at the bottom, and sits on a rather sweet black plinth. The internal absorbent material is mostly polyester wool, packed at various densities along the transmission line.

Cost? A very reasonable $1,025 (not including a year of weekend labour of 11 participants, estimated conservatively at $440,000 if we reckon the Audio Action members are worth $100 per hour each and that they slaved away for 8 hours each over 50 weekends). On the night the loudspeakers were driven by a 90 watt/channel hybrid integrated Consonance amplifier (valve preamplifier; transistor power end) which looked to me as if it was the a120 model in the Consonance line-up, fed by a Marantz SA15 SACD player. A quick check of Greg Osborn's webpage showed that the amplifier cost a mere $1,450. The SACD player is now a couple of years old, but it was not inexpensive when new: probably around the $2,500 mark? In other words, we were judging a system that cost in total in the vicinity of $5,000. Not cheap; but by no means extravagant.

And what about sound quality, Ron's primary consideration? The bass was, I thought, really very good. Its quality shown out during the first test track, Aaron Copland's Fanfare for the Common Man, during which the opening section with the pounding bass drum was pretty impressive; deep, fast and sounding like it should. I doubt you could get that quality (or quantity) of bass from any other $1,000 commercially available loudspeaker. Moreover, I can't think of many previous cases where a piddling 7" bass driver so effectively filled the Willis Room without straining too much. My initially positive impression was confirmed by the sixth test track, the George Gershwin piece, in which the double bass sounded quite lovely. I originally thought the treble was the weakest part, but that concern was swept away with the fourth test track, the scary Paganini Caprice 24. The violin was reproduced really very well, especially considering that the tweeter cost less than a halfreasonable bottle of McLaren Vale shiraz and the whole loudspeaker less than some people spend on a metre of speaker wire.

I had to leave at coffee time to get home at an hour that would allow me to take my son to the airport at 5 AM for an international departure, but one of the last test tracks I heard was Chris Jones' and Allan Taylor's rendition of the Tennessee Waltz. Those aluminium cones seemed to be made with a dobro in mind!

Against these positive sentiments, The Camel generated a type of sound that, if it were commercially available, I would not buy. To my ears (and bear in mind that my teenage daughter simply refuses to practice any music with me because she says 'Dad, you can't keep in tune, nor can you keep in time', so maybe I do have tin ears.) they did not have the warmth that I prefer. The midrange was very clear and precise and fast, but arguably quite forward. I prefer a touch less stridency. It is this very issue that led me on a path over the past 10 years to progressively replace my SACD player, amplifier and, eventually, loudspeakers with items that I hope will jell to make a system gorgeously seductive to listen to (rather than aiming for pure 'accuracy', whatever that means). Maybe it was my tin ears, maybe a consequence of those aluminium drivers, maybe it was some intrinsic character of the amplifier, maybe the fact that I was positioned to the far left in the Willis Room (unlikely, as I was then sitting decidedly off-axis), maybe the room itself was unfriendly?

Ron pointed out that they had tried all sorts of amplifiers with The Camel, with as expected a suite of different outcomes. If it was the amplifier match, I wonder whether the cold and slightly clinical midrange that I objected to could be fixed by using a valve amplifier running, say, KT88s or even better, EL34s? Something like a Prima Lunar might do the job fabulously, with the lush EL34s sweetening up the midrange a tad. The benign 6 ohm impedance and the highish sensitivity of The Camel would then come in a treat. You would have a tasty valve amplifier costing only $2,500 or so, running into a pair of more-than competent speakers that cost less than a grand. Can't imagine much better sound value than that. And The Camel's spouse-acceptance factor is not bad either: their aesthetics is such that I certainly would not be ashamed to have them in my house. They look professionally made and even quite nice to look at.

So, to conclude, June's meeting as a fascinating event. Ron gave a masterful overview of the difficult choices the Audio Action team had to make - and their final product was a trillion times better than the rubbish I built during my first forays into custom-speaker design.

Paul Boon

May 2017 Joe Rasmussen, Custom Analogue Audio, JLTi

Joe Rasmussen was so generous to us. He actually drove down from Sydney, bringing his gear. He has been in audio (including pro audio) for 40 years since the early 70s. [my notes are almost illegible here...]

He disagrees with Dick Small (of Theill-Small) to do with 75-odd ohms into speaker leads. He reckons people get damping factor wrong. Add resistance reduces damping. There is no such thing as "Damping Factor" (Q) and that resistance merely changes alignment. High Q gives a bass peak.

He likes current amps vs. Voltage amps. His $$$ mods to an Oppo 105 involve servo-controlled clocking. Buffer (analog) clock output. Jitter is everywhere, and you can hear it. Never eliminated, merely reduced. No negative feedback. Noisy inside a DAC. Clocking mostly clean. First clock most important.

Amplifier: Very low impedance. 53 KHz bias output. Speakers: Very flat impedance, 6 Ohms. Sensitivity 93dB /1Watt Kit $2750 w/o boxes. Two and a half way. MTM on top, series parallel to 400Hz atop triple bass (cf line source). Secret sauce conjugate filter crossover. Online "DIY-Audio" SoundEasy crossover Software, http://www.bodziosoftware.com.au/

Listening time: Don't explain (Caroline Henderson) "Plenty of love". Plenty of tone, frequency extension, presence.

"You want it darker" Leonard Cohen. Rather heavy bass balance or is it Cohen?

Kentucky Mountain Portraits (Mercury Living Presence), 1955 (-6dB /noise) Pretty darn acceptable music, unless compared with SOTA hifi nowadays.

Kari Bremnes Sjalusi "Losrivelse" 1993. Full range.

Shapeshifter, Santana, 2012 "Mr Szabo". Fast. Rich. Dynamic. Checked with iPhone AudioTools, RTA: Pretty smooth frequency balance.

Alan Wright (Sydney) also promoted thin speaker cables: wide bandwidth, no skin effect, and though losses are higher, they are even across the bandwidth.

Second amplifier: 45 Watt. 270 Ohm output impedance. No damping. Feeds current to the cones, loses all damping factor. Does current very well.

Morello Standard Time, Joe Morello, "Take five." Persuasive! Drum solo, Marilym Mazur (percussionist ex Miles Davis). Hit 100dB SPL.

F.E. Lorna.

April 2017 Mark Dohmann of Audio Union

April's monthly meeting was one that the presenter and MAC could be jointly proud of. Mark Dohmann, of Audio Union, and the two new turntables produced by that organisation, the Helix 1 and the slightly cheaper Helix 2. Alas, on the night of the presentation, said turntables were still somewhere on a container ship in the Indian Ocean, having been held up when it was decided - not unreasonably - to send them by sea (at a cost of $1,300) rather than by air (at a cost of $6,000). The good news, though, was that Mark could demonstrate a drop-dead gorgeous pre/power amplifier combination (the Dionysos pre-amp and a pair of 100 watt Class A Heros monoblocks), fed into a pair of equally gorgeous Lyra loudspeakers.

Before the equipment was auditioned, Mark spoke for nearly an hour on the two turntables. They are manufactured in Sofia (Bulgaria), under the aegis of the Audio Union, by Thrax. It's not often we see gear from the former eastern Europe, but that is not to underestimate the industrial design capacity of this part of the world. (Another example: the DAC - complete with separate rubidium- based atomic clock - from Antelope Audio in Romania.) Not only are there state-of-the-art machining facilities in Sofia, but wages are very much lower than elsewhere in the world, especially in comparison with those in the rest of the EU. Mark commented that had the Helix 1 turntable been built in Australia, it would have retailed for US$150,000; having it built in Bulgaria meant it could be sold for the (almost reasonably affordable) US$40,000 or Euro40,000. Mind you, he also noted that it would have been nigh impossible to build it here, as the support services required (e.g. supplies of very high quality aluminium alloys, expertise in CNC machining) are simply lacking for the most part. I guess that's what happens when a country ties its economic future to mindlessly exporting iron ore, coal, natural gas, bananas and dried-milk powder.

The Helix 1 and 2 turntables are designed by Mark as a member of the Audio Union, a loose assemblage of hi-fi people from Australia, Denmark, Germany, the USA and Bulgaria. The Audio Union symbol - Au - cleverly combines the international abbreviation for Australia, the chemical symbol for gold, and a hint of Audi, originally known as Auto Union. In turn, they are made in house by Thrax, the Bulgarian electronics house, which also constructs the auditioned amplifiers and speakers, among a suite of other audio equipment. Thrax builds not only high-fidelity gear but military and aviation stuff, and this gives them an unequalled exposure to state-of-the-art electronics and analytical techniques (e.g. in vibration analysis). Of course, Thrax is not alone in working this way: the English firm of dCS (Data Conversion Systems), arguably the producer of the most advanced DACs in the world, is really a radar specialist; I think that the company responsible for AVID turntables (also English - the name being the acronym for 'A Very Interesting Design') similarly makes highly machined products for a range of automotive, medical and military end-users. And my Copland amplifier, although nominally Danish, is actually made by Xena Audio in Sweden, a company with roots in avionics and military applications - hence the quality of manufacture and simplicity of design.

I imagine that all benefit greatly from their access to expertise in such nonaudio areas. An important difference is that the Audio Union and Thrax seem to approach their work with a devilish sense of humour: a review of the amplifiers on the Six Moons website notes that Thrax will also be making 'a limited 13-piece run code-named UO-26 for 26 unobtainium devices which aren't for sale and only for close friends and staff and as a prize for our best business partners' (see http://www.6moons.com/audioreviews/thrax2/1.html). Even the model names are quirky: the name of the Heros monoblocks 'derives from Heros Karabazmos, an ancient god of the underworld usually depicted as a horseman slaying a beast with a spear to be the likely precursor of St. George'; the Dionysis name, of course, remembers the horny, ancient Greek god of wine, sex, merriment, sex, food, sex, theatre, and sex. The Romans knew him as Bacchus, with a similar suite of pleasure-orientated interests. Maybe that's the link with audio: the pursuit of pleasure.

Mark was an admirable presenter; engaging, amiable, knowledgeable, clear, disarmingly honest. He discussed the reasons for choosing belt-drive over a direct-drive approach (but noted too that one customer for the Helix 1 turntable wanted it to run as a rim-drive: echoes of my old Dual 1216 turntable from the 1970s), and then why two belts (with different elasticity) were selected to improve speed stability. The choice of a servo-controlled DC motor came next, then the way the tube and the bearings of the tone-arm are con structed. Finally, he pointed out the essential characteristic: that the thing 'be allowed in the house'; in other words, that it be a thing of beauty as well as a technological marvel. And here I should add that the Helix 1 weighs a mere 60 kg. Mock-ups of the Helix 2 were then shown. This is a cheaper (US$22,000) version of the Helix 1, with the same platter, bearing and suspension, but with the provision for only one arm board and with a simpler servo control for the motor. Tivoli Audio in Camberwell is mooted to have both units on display in the near future - that is, when they arrive from the ship.

Then we had the pleasure of listening to five tracks played through the Dionysos/ Heros amplifiers and Lyra loudspeakers. The paradox was that, with the turntables thousands of kilometres to the west, the source was not direct analog but a transcription rendered through AIFF files and played through an everyday laptop computer via, I think, the Foobar audio player. But the ultimate source of the sound was a Helix 1 turntable, equipped with a very tasty Lyra Atlas cartridge. We heard excerpts from Tchaikovsky's Nutcracker, then Girl from Ipanema (sung by Astrud Gilberto), a piece by the English band Talk Talk (Spirit of Eden), Shelby Lynne's You don't have to say you love me, and, finally, the Beach Boys' In my room.

These were listened to with rare silence by the entire audience; with some other auditions I've seen the audience a bit fidgety, surreptitiously looking at their phones, occasionally whispering to their neighbours, flicking through their MAN, checking their watches, looking at the ceiling, scampering out for another cup of tea. Perhaps on those times the gear was simply not up to scratch or not set-up optimally, the choice of music not engaging enough, or the whole exercise throttled by the dubious acoustics of the Willis Room, which have much in common with those of an empty 44-gallon drum. Not this night: all I heard was a series of delightful, detailed, but effortless and untiring, pieces of music. The Nutcracker sounded almost believable; there was some very stylish snare-drum work on the Spirit of Eden track, and the Beach Boys' harmonies were as honey-like as ever. The session was called to an end at 9:45. Thanks to Mark for a truly enjoyable - and informative - evening. May the whole Au enterprise thrive.

Paul Boon

March 2017 A Night with Hugh Dean, Aspen Amplifier Designer

Ten thirty PM at this month's GM. Loud socialising at tea time. Nick's method to remind us that there was more to be heard from Hugh Dean and his latest AKSA amplifiers: play music from Dead Can Dance very loud to penetrate the hubbub of tea time conversations.

Eleven months ago Hugh Dean demonstrated his Aksa amplifiers to the club. For the March 2017 meeting he brought the latest Maya and Saksa amplifiers. Inside the latest casework are new designs using quality pcbs and the minimum number of components required to achieve the design goals.

What has not changed is Hugh's obsession with pcb layout and assembly. The boards for the Maya are works of art, the rear of the board has an opaque protective coating, Only eight transistors per channel drive two large MOSFETS to an output of 320 Watts per channel (four Ohms) stable into reactive and low impedance loads.

The use of only two devices in the output stage is to accurately recreate the depth and width in the recording. Hugh's reasoning is "more devices in the output stage to supply high power after feedback turns soloists into choruses". Another quote from Hugh is about distortion. "Engineers measure everything. That is, they reduce distortion to aid measurement of THD (total harmonic distortion) including all orders of harmonics. If the proportion of 5th 7th and 9th harmonics is high compared to 2nd and 3rd harmonics music sounds like s fire siren".

Much was discussed about distortion in valve and solid state designs. Valve amplifiers usually have less gain and global feedback than solid state designs. Valve amplifiers can have the sum of second and third harmonics around 95% of the total harmonic distortion. In his experience Hugh believes high levels of the higher order harmonics are not found in nature. That is a cause of listener fatigue with "low distortion" amplifiers.

As Hugh said last year: "After 25 years I'm getting pretty good." And his quote from Nelson Pass "If you want it to sound like a tube, use a tube".

Kef 105 Reference loudspeakers were supplied by Ray from HiFi Exchange. The setting up of the system was by Nick and was tuned to give the best imaging and bass. [Hugh commented that the bass from the rather vintage KEFs did not show his amplifier at its best. ..Ed]

Dave Shaw

February 2017 Convoy International & Klapp visit the Willis Room

First let me declare a bias, I own a pair of B&W speakers. We were introduced to B&W manufacturing with a short 5-minute video of the manufacturing processes.

A near capacity membership settled in, starting off we listened to the B&W 805 D3 stand mounted speakers. These were elevated by small stand, beneath the regular stand, to raise them to our ear levels. As we know the Willis room is a very unforgiving acoustic room.

    Shelby Lynne singer with her CD title and track "Just a little loving". The rim shots and cymbals were clear.
    Kurt Wagner, singer, with his band Lambchop played "is a woman" from the CD of the same name. Somewhere described as with his "swooning and saw dusty vocals".
    Joshua Bell, & Frankie Moreno? Plays "Eleanor Rigby" Not sure where this was recorded.
    Gregory Porter sang, "When Love was King".
    Piano concertos 4 & 5 Coyote Kobe.
    With Christ Baron singing "Columbus" ended the first half.

In a small apartment these would suite very well. This speaker was very clear and agile with the diamond tweeters, which were so clear and crisp. The latest flagship model B & W 800 D3s were connected up next, and inbuilt spikes wound down into the floor, this caused us to feel some of the bass vibrations through our feet.

Frankly there could not be a bigger contrast in speakers. This had two huge 12" bass Aerofoil cone speakers, a Nautilus Turbine head contains a Continuum cone, for the mid range, and a diamond encrusted tweeter.

B & W say the 800 D3 is the best they can currently do to create a perfect as possible speaker,- the "pinnacle of audio perfection".

    Up first was Jennifer Warnes singing from The Hunter, a warm rich full-bodied sound.
    Nain Bach Track 2 - Society of Sound (B&W's online music downloading service)[Nain (pronounced nine), which means grandmother in North Wales, Bach means little, also a term of endearment.]
    The Hunger Games, music by James Newton Howard.
    Music from Becks' Best Album of 2014.
    Arturo Pizarro pianist, Beethoven Piano Concerto.
    Muddy Waters "Leaving Chicago" 1961 Track 1.
    Antonio Forcione playing guitar, track entitled "Acoustic Revenge".
    Edwin Holland track titled Low Expectations.

These are BIG speakers, a big presence in any room. My wife, who for the first time was present at a MAC meeting, said to me afterwards, "No way could she have them in our house"! Alas SWMBO!! But these had such superb definition and a wonderful natural sound clarity.

Peter Oakley, our Roving Golden Ear

January 2017 Buy, Swap and Sell

Another Buy, Swap and Sell night went well. Pizza and drinks were enjoyed by all.

Web Ed.