[Dick Pierce]

On Jun 20, 1:42*pm, "Harry Lavo" wrote:
"Sonnova" wrote in message
speakers. While measurements can tell one a
lot about speakers, ultimately,
you have to listen. Same with cartridges.

Those thinks told you a lot...sure the overshoot told you
that they were ringing at some frequency

Actually, it tells you nothing of the sort. A system
with both flat amplitude response and flat phase
response in the pass band will have no resonances
AND will have ringing. Consider the well-known Gibbs
phenomenon where simply truncating the number of
terms in the series will result in symmetrical ringing:
the response is both the amplitude- and phase-domain
is absolutely dead-nuts flat with no resonances.

but if it was a single overshoot and well damped
thereafter, then you knew the cartridge was
properly designed and would probably sound
pretty good. *Those that rang "forever" were
underdamped,

Wrong. Unless you are arbitrarily changing the
definitions of "damped," which are quite well
established without the misguided aid of the
high-end realm, ANY overshoot indicates the
system is under-damped.

and those that had a soft leading edge were
overdamped or had badly rolled off high ends

This example of discussion of "rise time" and
"over damped" and "under damped" and all
that is illustrative of what's wrong with the high
end realm and "measurements." I don't mean
to pick on you specifically, Harry (though I might
be accused of using you as an example), but
this is a case of knowing just enough to have
the buzzwords but not enough to have it mean
anything.

"Rise time" is but one, and on VERY narrow and
limited measure that, by itself, means nothing.
If you're looking at transient response, a better
measure is total settling time: which not only
include the rise time, but ALSO includes the time
for any overshoot to approach within some accepted
limits of the final value.

Minimizing rise time leads to severe response
anomalies in the frequency domain and being
such a limited measure, has no means of defining
an optimum value. Instead selecting a criteria such
as the minimum time to settle to the final value
gives you an optimization goal. And that's something
that's quite easily defined.

The result is that since the high-end cutoff of a
phono cartridge SYSTEM is effectively a 2nd-
order low-pass, and since such present a minimum-
phase response, we CAN say the the optimum
transient performance of such a system occurs
when the Q of the cutoff is approximately 0.58.
This is the critically damped point, the response
which provides the best transient performance
(minimum transition and settling time).

(most moving irons due to capacitive loading). *

So fix the load capacitance. Why is the incorrect
load capacitance such an issue, given how easy
it is to fix. The vast, vast majority of MM phono
inputs compined with the vast, vast majority of
cable harnsess have to LITTLE capacitance, so
it's a trivially easy fix.

I wasn't too surprised to find, therefore, that it
had a very fast rise-time

And I'll assert, with a couple thousand person-
centuries of of experience, theory and practice
to back it up, that the rise time is defined as much
IF NOT MORE by the input signal than by the
response of the cartrdige system. Explain, for
example how it can be any faster than the input
signal.

Square wave response tests have the advantage
of being quite easy to generate, quite easy to view,
and especially easy to (mis)interpret. As a real
measurement tool that's capable of revealing any
information, square waves are extremely limited
in utility and content. The complex transfer function
will tell you everything a square wave does, and
much, much more and without the huge interpretive
ambiguity of square waves.