In article , Andy Evans
wrote:
An amplifier should not have a voice.

Maybe in theory, but in practice componants sound different and amps
sound different, and 'voicing' an amp is the common term used in its
development.

As I said earlier, this is not my experience in general. :-)

I should say, though, that I tend to prefer designs that have a low output
impedance, flat response, unconditional stability, etc.

I've had a few conversations about how Beard amps were
'voiced', for instance, with one of their chief designers. In terms of
valves, the common term 'tube rolling' would not exist if it were not
for the fact that tubes sound different - swap a 6J5, 6L5, 6C5 and 6P5
and you'll have subtly different sounds, not even to mention varieties
within each type like metal, G and GT, round anode, flat anode, care in
manufacture, production run etc etc.

This prompts me to ask: The only figures I have for things like valve
microphonics measurements are in old Mullard mags. Are these available for
modern valves, comparing the different makes, and showing typical
variations, etc?

Such threads on tube rolling and voicing fill the pages of
www.audioasylum.com. To suggest that this representative bunch of
electrical engineers, chemical engineers, nuclear physicists and just
plain DIY amp builders with many years of building experience don't know
what they're doing is surely stretching credulity just a bit too far.

Afraid I'm not a 'physicist' any more. I retired last month... :-)

Slainte,

Jim

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