Date:         Sat, 30 Jun 2007 23:04:11 -0500
Reply-To:     Association for Recorded Sound Discussion List
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Sender:       Association for Recorded Sound Discussion List
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From:         Bob Olhsson <[log in to unmask]>
Subject:      Re: Is The Record Shop Dead?
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-----Original Message-----
From Steven C. Barr: "... As I understand it, the 44.1KHz sample frequency
is supposed to produce an adequate version of the actual analog signal
such that our human ears and mind can't hear any identifiable
difference...?!

On the other hand, there DOES exist an identifiable and demonstrable
difference between vacuum-tube and solid-state audio equipment! Oddly
enough, this difference exists because most audio amplifiers operate
with audible/identifiable distortion. Tube amplification simply decreases
in efficiency is limits are approached...producing a distorted signal
waveform, but one without any "sharp corners"...! Solid-state amplification,
OTOH, simply reaches its limit and quits amplifying any further...leading
to "sharp corners" in the waveform..."

I'd like to correct a couple common misunderstandings.

First off, we got 44.1 because it was the highest sample rate that off the
shelf video equipment could edit and off the shelf video disk technology
could replicate. It was well known at the time that 44.1 would be a
compromise in any real-world implementation. This was why 48kHz was chosen
for professional applications and most theorists believed sample rate needed
to be pushed as high as 60kHz. to actually eliminate all artifacts within
the audible range.

While tube equipment shows different distortion characteristics, the real
reason people preferred it was that it had a significantly wider useable
dynamic range as opposed to the "pleasing distortion" claimed by the
salespeople. Solid state offered huge profit margins leading manufacturers
to choose specs that made it look better but if you measured how the
equipment was actually being used, the spread between audible noise and
audible distortion of tube gear could be as much as 25 dB. better.
Unfortunately the dynamic range of most contemporary tube gear is worse than
most contemporary solid state gear and people are bragging about the
pleasing "warm" distortion. Misleading advertising from 40 years ago is now
passing for truth.
	

Bob Olhsson Audio Mastery, Nashville TN
Mastering, Audio for Picture, Mix Evaluation and Quality Control
Over 40 years making people sound better than they ever imagined!
615.385.8051 http://www.hyperback.com