It's a great pity I can't be there.... but there is a chance, could I come too, Andy, if I can make it?
Hi Theo,
When you ask questions about how my amps and preamps work together, you go to the nub of the design process. Frankly, I can't answer you. But I do know that since I use my amps and speakers during development of my preamps, then you'd expect 'em to go well together since I do a lot of listening tests after I establish the engineering limits of operation of the circuits.
The conflict between the objectivists and the subjectivists (I'm both) is trenchant. You should be able to define precisely how something will sound from a careful measurement of frequency response, slew rate, total harmonic distortion. But you can't. Some of the best sounding amps in the world - single ended tubes - have distortion in the 2-5% range! Clearly more detail is needed in measurement, and I suspect that a careful breakdown of the distortion artefacts is needed to progress further. As well, I'm convinced electronic circuits behave differently with many frequencies passing through them than simple test tones, and the theory of memory distortion, proposed by Lavardin, a French amplifier company, supports this.
In the absence of definitive evidence correlating good measurements with good sound, amp design becomes an unholy mixture of art and engineering. In time, perhaps the next ten years, these issues will be clarified, but until that happens, the guy who develops amps along both lines - objectivist and subjectivist - will likely have an advantage because he will, at least in part, be accounting for many of the subjectivist issues which the audiophile buyer considers almost exclusively. I'm always struck by the tacit acknowledgment of savvy audiophiles that specs say nothing. They rely almost exclusively on protracted listening tests. This to me is right on the money. That amps are usually developed entirely on objectivist grounds is a statement of the power and influence of the engineering fraternity who develop them; a resounding vote for their expertise perhaps and a comment on the marketing techniques used to sell them.
I look forward to returning to Oz; the last 24 hours I've been laid up with a very unpleasant virus which had me bedridden, unable to eat for the duration. Today we have the long journey via Singapore to Oz, I can at least walk now, but it's been a trial. If trips to Indonesia are always accompanied by illness, and I've had Bali belly for just over two weeks, I will need to consider carefully.... but as an experience, this has been seminal, one of the true revelations of the Far East, in 25 years the birth of a middle class in Indonesia.
Cheers,
Hugh
