Jim Lesurf wrote:

I've just put up a new web page at

http://www.audiomisc.co.uk/HFN/Squar...quareDeal.html

that looks at the use of squarewaves for assessing
amplifiers, etc.

Prompted to do this by noticing squarewave results being
used to present
ideas about speaker cables, and realising that the humble
squarewave has
largely fallen into disuse.

I've also tweaked the site a bit, and hope to make a few
other minor
improvements and alterations soon.

Slainte,

Jim


The cd-player source argument is a red herring, surely?
Especially combined with the arbitrary example of a 5k
square wave. 1k would give you plenty harmonics, especially
if you weren't daft and used a proper source.

You conclude that reviewers have abandoned the square wave,
but did they ever use it much anyway? A square wave test
result seems to me several levels of abstraction distant
from what the average audio enthusiast might be interested
in. It offered a convenient method of testing amplifiers for
designers or home builders with limited equipment. It was
never ideal because it superimposes several tests such that
results need careful interpretive disentanglement.

When did it become common for 'scopes to have memory?
Perhaps it then became unnecessary for the pulse to be
repetitive.

With a single pulse and a 'scope with memory to capture its
consequences, the entire transient response, HF and LF, can
be seen, without interruption by successive pulses.

Ian