In article , John Phillips
wrote:

So, in summary it seems that there are some causes of time-domain audio
signal ripples ("ringing" as a description of the observed phenomenon)
that may indicate problems in an audio system. One of those problems
may be "ringing" as a cause of the observed phenomenon, associated with
marginal stability in both an analogue and a a digital sense.

I'd say the distinction here is between a symptom - visible ripples or
ringing associated with something like a transient - and assigning a
'cause' of that observed behaviour. The problem is that there are various
possible causes.

However it also seems clear that the Pavlovian response sometimes seen
in audio contexts to the observation of a "ringing" waveform is probably
not necessarily appropriate.

Yes. In practice this is perhaps another example of a common problem in
areas like domestic audio. That a commentator may decide they have spotted
a symptom, and then jumps to a conlcusion about the cause - perhaps being
completely mistaken. Similar to the case of 'Dirty Digital' in another
thread, where someone does a measurement in an inappropriate manner, and/or
misunderstands the results they see. The symptom (FFT analyser display in
that case) is correct - for the given situation - but this symptom then
prompts an incorrect diagnosis of the cause. :-)

Alas, it is one thing to give someone a lot of nice test kit. It is
something else for them to use it correctly, and recognise what the results
do (or do not!) tell them.

Slainte,

Jim

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