Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10 5/3/83; site cdi.UUCP
Path: utzoo!linus!decvax!tektronix!reed!cdi!caf
From: caf@cdi.UUCP (caf)
Newsgroups: net.audio
Subject: Re: Dynamic Range Estimate
Message-ID: <242@cdi.UUCP>
Date: Fri, 12-Aug-83 15:41:11 EDT
Article-I.D.: cdi.242
Posted: Fri Aug 12 15:41:11 1983
Date-Received: Tue, 16-Aug-83 21:35:07 EDT
References: <1074@dvamc.UUCP>, <286@hound.UUCP>
Organization: Computer Development Inc, Beaverton OR
Lines: 28

Subtracting the ambient noise level of the listening room from the peak sound
level of a stereo system does not yield a valid figure for the perceptual
dynamic range of the setup for at least two reasons:

1.  The listener localizes sounds with binaural hearing.  The whirr of
an icebox in the next room can be distinguished from the program material/hiss
in much the same way that most people can pick out conversations in a cocktail
party.
2.  In addition to (1.), the ambient noise in the listening environment is
often in a different frequency rage from the music and/or hiss emanating
from the loudspeakers.

The last time I autitioned CD's was in a showroom with a rather noisy air
conditioner and indeed I couldn't hear any hiss on the CD's with risking
louspeaker armageddon.  However, at home, when things are quiet (with the
icebox off, etc.) I can sometimes hear the slight noise background from
digitally mastered DBX records cut in/out between selections.

When playing the best digitally encoded DBX records, the only "noise" I
really notice (aside from occaisional ticks and pops) is that made by
the conductor and orchestra in the process of playing the piece.
This makes the recording enjoyable and realistic to me.

As far as CD's for myself, I plan to hold off (and susbist on my collection
of DBX records) untill Pioneer introduces its combo LV/CD player.

-- 
Chuck Forsberg Computer Development Inc Portland OR cdi!caf (503)-646-1599