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From: mat@mtx5a.UUCP (m.terribile)
Newsgroups: net.audio,net.auto
Subject: Re: Phase distortion on music
Message-ID: <1211@mtx5a.UUCP>
Date: Mon, 24-Feb-86 00:00:26 EST
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Posted: Mon Feb 24 00:00:26 1986
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> > 1 (hack, cough, wheeze) speakers.  It wasn't that bad at low volume.
> > However, most car stereo amplifiers have gross phase distortion (pull out
> > your Ford factory radio and run a proof on it) as well as a frequency
> 
> The human ear is insensitive to phase and will not be affected by phase
> distortion, provided the amplitude vs frequency characteristic is not altered.

This is conventional wisdom.  And it's true -- phase distortions
are irrelevant to the intelligibility of speech, and to music so
long as other distortions predominate.  But in much of today's
really good equipment, other distortions do not always predominate.

Tests a while ago (someone know the actual reference) indicated that
phase distortions CAN cause subtle but audible changes in timbre when
they occur between about 100 and 2000 Hz, with the most sensitive
region being about 600 to 1200, if I recall.

You also mention the RIAA equialization doing violence to relative
phase.  Well, perhaps this is what the vinyl-over-CD freaks are
so used to? (or why Carver was able to measure funny differences
between vinyl and CD?)
-- 

	from Mole End			Mark Terribile
		(scrape .. dig )	mtx5b!mat
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