I am messing around with comparing the frequency response curves of
two musical instrument preamps -- one commercial and one homemade. The
commercial preamp has a pronounced curve, and cannot even be adjusted
into flat response. Mine is essentially flat when the tone controls
are centered, since it is basically a hi-fi design. I can persuade
myself that they sound different, but we all know that perceptions are
colored by expectations. Naturally mine sounds better ;-)

At what point can I say that two curves are different enough that it's
not worthwhile bothering with a blind test? In this case, it appears
to be more than a few dB, to the point where I'm not even sure how I
would define the signal levels in order to match the levels.

This is not directed at subtle differences between high fidelity
amplifiers, but is strictly limited to the ugly world of musical
amplifiers.

In article ,
(Detector195) wrote:

I am messing around with comparing the frequency response curves of
two musical instrument preamps -- one commercial and one homemade. The
commercial preamp has a pronounced curve, and cannot even be adjusted
into flat response. Mine is essentially flat when the tone controls
are centered, since it is basically a hi-fi design. I can persuade
myself that they sound different, but we all know that perceptions are
colored by expectations. Naturally mine sounds better ;-)

At what point can I say that two curves are different enough that it's
not worthwhile bothering with a blind test? In this case, it appears
to be more than a few dB, to the point where I'm not even sure how I
would define the signal levels in order to match the levels.

This is not directed at subtle differences between high fidelity
amplifiers, but is strictly limited to the ugly world of musical
amplifiers.

It depends a lot on where those curves are.

Sensitivity to response curves isn't hard to test. Have somebody fuss
with a 10+ band EQ while you listen but not look. What can be tweaked
without you knowing?

Distortion is a whole different can of worms. There are many types of
distortion and many of them can coexist or vary with frequency. This is
where marketing terms come in to describe complex alterations that can't
scientifically be proven to sound better or worse.

"Detector195" wrote in message
m


At what point can I say that two curves are different enough that it's
not worthwhile bothering with a blind test? In this case, it appears
to be more than a few dB, to the point where I'm not even sure how I
would define the signal levels in order to match the levels.

Please see the chart posted at http://www.pcavtech.com/techtalk/FR/index.htm
..

"Arny Krueger" wrote in message ...
"Detector195" wrote in message
m


At what point can I say that two curves are different enough that it's
not worthwhile bothering with a blind test? In this case, it appears
to be more than a few dB, to the point where I'm not even sure how I
would define the signal levels in order to match the levels.

Please see the chart posted at http://www.pcavtech.com/techtalk/FR/index.htm
.

That is exactly what I need. Taking another look at the curves for the
commercial preamp, I am beginning to think that it must be
malfunctioning.