Re: Crossover distortion and NFB

From: N. Thornton (bigcat_at_meeow.co.uk)
Date: 10/28/04 

Date: 28 Oct 2004 05:48:57 -0700

kensmith@green.rahul.net (Ken Smith) wrote in message news:<clfa90$54k$1@blue.rahul.net>...
> In article <bpEed.17820$nj.950@newssvr13.news.prodigy.com>,
> Joerg <notthisjoergsch@removethispacbell.net> wrote:
> [...]

> >Tubes? Well, they just sound great. Then there is that glow, a little
> >hum, a crackle now and then. Anyway, feedback also works great with
> >tubes. For some reason it wasn't done a lot in their days.

> When you have to pay an hours wages for a gain of 10, you are a lot less
> willing to give it up than when it costs you less than 1 seconds wages.
> Tubes cost a lot to make even back then.

Yes, though even more than that in fact. One stage of amplification
would normally cost well over a weeks wages, and those valves didnt
last forever. Pfb was big business, just about no-one took nfb
seriously. Hence the development of circuits that amplified the rf,
detected it, then fed it back as audio through the same set of valves
a 2nd time round :)

NT

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