"Don't choke. Don't choke, please don't choke." If you've seen Paul Bettany in Wimbledon, you know the scene. He's a journeyman tennis player who finds himself at the Wimbledon finals facing a younger, hungrier, fitter and faster opponent. His own love interest (who was romantically involved with his nemesis on the court) seems to have deserted him and Paul just can't seem to find the will to win.
|Mick Maloney of Supratek in Australia has launched his first production amplifiers, the 50wpc Malbec and 100wpc Mondeuse. Just as he does for his famous preamps, Mick|
|seems to be doing things differently once again. During an e-mail exchange about these amps, he made an innocuous remark that really drove home. It started by me contemplating how he could achieve his claimed 0 (or even negative) output impedance to get transistor-type damping factors. Doing a little research, I volunteered for positive current feedback like the big Wolcott amp seems to apply. The Wolcott is famous for driving full-range panels that eat alive every other tube amp extant and carries the patents to prove it.
"Yes, but Kevin Covi and I came up with a way to do it very simply and hence very transparently. The Wolcott is a technological marvel but very complex, with the sonic attributes of complex designs. My Mondeuse has one 6SN7 driver and still achieves 100 watts with a Supratek preamp. The tube complement is 1 x 6SN7, 4 x KT88 and 2 x 5AR4. That's it. It can drive difficult speakers that usually require complex and choked amps. This amp lets them breathe and the results can be very similar to what you're getting with your Zus in terms of ease and dynamics. This amp transforms speakers that you thought okay into monsters. I have a pair of Spendor BC-3s which, while enjoying a good reputation, often just don't perform accordingly unless you throw huge power behind 'em. They are just wonderful with the Mondeuse. And these amps do the same thing with lots of speakers that are ordinarily ... well, ordinary."
I could relate to the choking part. That's been my issue with tube amps that apply tons of "regulation" as it were (my non-technical term to encompass everything that strangulates the musical flow). They tend to choke up a bit. They may measure well and not be guilty of the usual errors but then they commit their own (which, musically speaking, can be just as objectionable as the fidelity errors the common designs commit on most speakers).
Mick concurred. Exactly! And that is why we all went to high-efficiency speakers. Because we could use simple amps that don't choke the sound. But with our new approach, we can use "difficult" speakers that have excellent response and get the very best from them. Of course there are still advantages and disadvantages to both methods but for the average man with his modern-day speaker, it's a real advantage.
Did you notice the innocuous bit?
Maloney, in a very offhand manner, threw in that the reason some of us have gravitated toward high-efficiency speakers is not really the speakers. It's the amps they allow us to use. Perhaps that's indeed been obvious to you all along. Yet for some reason, I've personally been fixated on the speaker to explain why I fancied the final outcome.
|I've always loved Chuang-Tzu's Taoist missive. "Easy is right, right is easy - when the shoe fits, the foot is forgotten." Here's the audiophile equivalent. In an earlier e-mail exchange, Mick also explained how most amplifiers these days are really integrated amps. They insert additional gain stages ahead of the power buffer to become de facto preamp stages - integrateds. Strap an active preamp in front and you've got excess gain, excess noise and excess circuitry. In the Supratek scheme, the preamps are very high-gain devices. This eliminates the need for additional gain stages in the new Supratek amps (excess amplifier gain is popular because it allows the application of high negative feedback as well as driving such amps source-direct).
|Mick uses a pair of Supratek custom electrostats as part of his resident speaker arsenal to test his electronics on. He claims that driving those stats from his Mondeuse, the sonics are equivalent to his high-eff/low-power SET setup - and in certain aspects even preferable because of better linearity and lower distortion in the transducers. The secret to transposing the breath-of-life aroma to non-SET speakers is, he claims, to use his new amps. Mick has always admired the Wolcott amp for breaking previous technological barriers. Its performance seems|
|measurably load-invariant, something that's simply not the case for most any tube amp ever made. Load invariance could fairly be described as any amp maker's ultimate dream. It means completely stable, predictable, same performance no matter the speaker or SPLs.
By the same token, such amplifiers have often been accused of lack of finesse and a somewhat mechanical mien. Over-regulation I call it. If Maloney's claims are true, then we've now got tube amps that behave like muscle amps but sound like SETs (and Mick has built SETs to know). At $3,000/pr for the 50-watt Malbec monos in standard trim, we're not entering monster amp pricing either. If you've been looking for a good audiophile detective story, this one's got the earmarkings of an exciting -- and as yet unwritten -- ending. Hercule Poirot on the Trans-Australia Express?