In article , JustMe
wrote:
In the "Amp swap disappointment" thread, below, Ian has said that it's
possible to accurately measure the differences between each amp and, I
would assume, judge just what it is about one amp that might make it
preferable to another amp, to some listeners.

Would it therefore be possible for someone to take a "straight-line" amp
- and I'm happy to accept whatever you judge to be a representation of
the closest example of this - and then build an add on "filter" to alter
its sound to reproduce the sound quality of the Alchemist?

In principle, yes, although the definition of what is required would
probably have to be broader than a 'filter'. In practice, difficult, as a
number of properties may be involved. Some may not be correctly identified,
and others may depend upon the conditions of use.

Then, maybe, a dozen or so other popular amps could be measured, and
filters built to represent each amp in turn.

Would I be able to hear the difference between the "straight-line" amp
with the Alchemist filter and the Alchemist amp?

Can't say as it would presumably depend upon how well the "filter" actually
represents the totality of the processes the Alchemist is performing.

What you *could* do, though is something like the following.

Play music through the Alchemist into a pair of speakers. While doing so,
connect leads to the speaker terminals and record the signals there onto
CD-R using a reasonably quality recorder. Note the signal level with a
meter.

The replay the recorded version of the signals using a different amp that
is known to have a flat response, low distortion, and low output impedance,
adjusing the level at the speakers to be as before. Then judge how similar
it sounds.

Repeat this process, but reversing the positions of the amps. Or using one
of them 'twice'. Compare, contrast, discuss. :-)

Alternatively, it would be possible in principle to do a 'live' version of
the above and avoid recording, although this would be more complex to set
up. Might make it easier to do a 'blind' check, though...

Slainte,

Jim

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