Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site hp-pcd.UUCP
Path: utzoo!linus!philabs!seismo!hao!hplabs!hp-pcd!hpfcla!hpcnoa!rmd
From: rmd@hpcnoa.UUCP
Newsgroups: net.audio
Subject: Re: Improper mixing on pop CDs? - (nf)
Message-ID: <2431@hp-pcd.UUCP>
Date: Sun, 13-Nov-83 03:26:38 EST
Article-I.D.: hp-pcd.2431
Posted: Sun Nov 13 03:26:38 1983
Date-Received: Tue, 15-Nov-83 00:33:59 EST
Sender: notes_gateway@hp-pcd.UUCP
Organization: Hewlett-Packard, Fort Collins, CO
Lines: 32

#R:bbncca:-27200:hpcnoa:3500008:000:1348
hpcnoa!rmd    Nov 11 18:40:00 1983

I have noticed this phenomenon on pop CD's.  I spent a couple of
hours one night playing a CD and an LP simultaneously, switching
back and forth, playing with the equalizer, etc.  There seems to
be something like 3-4 db more high frequency energy on the CDs.

However, it is not strictly a matter of different of different
equalization.  Turning the treble up on the the LP does NOT
make it sound like the 'flat' CD nor does turning the treble
down on the CD make it sound like the 'flat' LP.  There is
still a very noticeable difference which is somewhat difficult
to describe other than to say that when the total amount of
high frequency energy is equalized, the CD sounds more 'clear'.

I suggest that this is due to two causes:  1) the frequency 
response of the CD and the entire process used to produce it
is flatter than for the LP; and 2) the dynamic range of the CD
is noticeably greater.  Since much high frequency energy is due
to percussion or guitar strings, higher dynamic range will 
increase the apparent level of high frequencies.

For the particular CDs I have, I much prefer CD to LP.  I am
somewhat curious about the person who prefered to listen to
the LPs because of the high frequency problems.  Did he try
turning the treble down on his system?  Is his system overly
'bright'?
        
        -Rick Dow
        hpfcla!rmd