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Path: utzoo!linus!security!genrad!decvax!harpo!eagle!allegra!alice!rabbit!jj
From: jj@rabbit.UUCP
Newsgroups: net.audio
Subject: Re: Amplifiers for CD players?
Message-ID: <2165@rabbit.UUCP>
Date: Thu, 3-Nov-83 16:22:50 EST
Article-I.D.: rabbit.2165
Posted: Thu Nov  3 16:22:50 1983
Date-Received: Sun, 6-Nov-83 17:23:48 EST
References: ihuxm.668, <302@whuxk.UUCP>
Organization: AT&T Bell Laboratories, Murray Hill
Lines: 46


To elaborate slightly on Bill Mitchell's article:
	Amplifiers that have a lower dynamic headroom
rating, but a higher power rating, may be just as good,
since (for example) take:
	Amp 1.. 50 watts Continuous Power. (RMS power, foo!)
		Headroom of 3 dB
		-->  100 Watts peak, for short periods

	Amp 2.. 100 Watts FTC continuous power
		Headroom of 0dB
		--> 100  Watts peak, for short periods.

The only differences between these two power amplifiers
(in circuit terms) are likely to be:
	1) Larger filter capacitors(stiffer power supply)
	2) Bigger heat sinks (and thus more thermal stability)

Given the better power supply and the bigger heat sinks, I would
always take the bigger amplifier, with the lower headroom rating
<assuming that the respective peaks are the same>, given that other
performance considerations are the same.  The more heavily built
amplifier is likely to have several durability advantages.

I also tend to disagree somewhat with the idea that organ music has
huge peaks (compared to its average power.)  With a few exceptional
organs, this is true, but with most (either classical, romantic(ecch),
or baroque) organs, the dynamic range isn't that big.  None the less,
the accoustic power (and hence the maximum output power required, both
of amp and speakers) is *T*R*E*M*E*N*D*O*U*S*.  A lot of disc recordings
of pipe organs deliberately filter out the lowest rank of pipes (32 foot,
yes I know that there are a FEW 64 foot ranks, but...) and compress
the remainder to make the record cutting easier.  (It is quite difficult,
because of the de-emphasis involved, to record VERY low bass, at
high energy levels.  Most "rock" doesn't come close, since
the bass guitar gets to 44Hz(at best), and even 16 foot pipes (open ended,
not stopped) reach  32 Hz.  )This leads, in many
cases, to really boring recordings. <That will not nuke the average speaker,
incidentally.>  

Down with compression!
-- 
 o   O   from the pyrolagnic keyboard of
   ~              rabbit!jj
 -v-v-
 \^_^/