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From: newton2@ucbtopaz.CC.Berkeley.ARPA
Newsgroups: net.audio
Subject: Re: Compressing/Limiting Amplifier
Message-ID: <915@ucbtopaz.CC.Berkeley.ARPA>
Date: Wed, 1-May-85 01:40:50 EDT
Article-I.D.: ucbtopaz.915
Posted: Wed May  1 01:40:50 1985
Date-Received: Fri, 3-May-85 04:15:18 EDT
References: <2620@drutx.UUCP>
Organization: Univ. of Calif., Berkeley CA USA
Lines: 22

I can't believe it-- a question about *audio* instead of bombast about
bullshit!

Let me just brush the dust of centuries off this tablet-- there! OK, first of course
you'll want to gang both stereo channels (so your precious stereo image doesn;'twander when one channel's gain changes WRT to the other).

Second, just what are you doing with a 15 watt FM transmitter? If it's a translator
or repeater, fed by a broadcast program, the modulation should already be limited,
so I'd guess you'd only "need" a safety limiter to guard against improper
gain-setting. Come to think of it, you said "when I'm talking", didn't you?
So I'd advise first of all a clipper (or limiter, to use the polite term)
to avoid wasting all your dynamic range on the useless fricatives and glottal
stops (git th' tar 'n' feathers, boys, he's a-stompin on our dy-namic range..).
If that doesn't allow a decent average loudness without instantaneous overmod,
you might consider adding compression to taste. If you're using the US standard
75 microsecond preemphasis, you might give some thought to a frequency-sensitive
compressor that is less tolerant of spectral components most likely to overmod-
ulate. The late and apparently unlamented Dolby FM system will reward study.

Yours for less crap about imaginary problems and their illusary solutions,

Doug Maisel