"John Woodgate" wrote in message
...
: I read in sci.electronics.design that Kevin Aylward kevindotaylwardEXTR
: wrote (in
: .net) about 'A little feedback worse than none at all?', on Wed, 19 Nov
: 2003:
: Err.. John and me are arguable, friends. My comment was not at him
: personally, but at what he said. What he said was crap.
:
: No, Kevin, it isn't. What happens when you apply lots of feedback around
: an amplifier of poor linearity is that you swap maybe 5% of low-order
: distortion (2nd, 3rd, 5th.) for 0.05% or so of every harmonic up to the
: upper band limit of the amplifier. The latter sounds FAR worse, because
: of the multiplicity of intermodulation products, some of which are much
: larger in amplitude than the adjacent harmonics.
: --
: Regards, John Woodgate, OOO - Own Opinions Only.
http://www.jmwa.demon.co.uk
: Interested in professional sound reinforcement and distribution? Then go
to
: http://www.isce.org.uk
: PLEASE do NOT copy news posts to me by E-MAIL!

Here is one problem of the concept of feedback itself:
it is all very well to model perceived physical phenomena
in a suitable mathematical form, convenient to 'get rid of'
time by using complex numbers, but

a cause-effect-feedback chain of events does not occur in zero time,
whatever your modeling might lead you to believe.
So here is one, just for Kevin:
what are you actually correcting there with a feedback signal ?

Cheers,
Rudy