Klarinet Archive - Posting 000092.txt from 1994/12

From: OLIVER SEELY <oliver@-----.EDU>
Subj: Re: digital recorders
Date: Wed, 7 Dec 1994 17:14:05 -0500

In the June, 1994 and November, 1994 issues of Audio Magazine
there are reviews of Sony DAT and Minidisc systems respectively.
I generally mistrust reviews in magazines dependent upon
advertising revenue -- they never say anything too bad about
the products (generally), but these two reviews make interesting
reading, in any case. Both systems record and playback
with superb fidelity. The author of the Minidisc article
prefaces his criticism of the minidisc system by saying that
he long ago learned to mistrust his audio memory (!), and then
goes ahead and gives the system some mild criticism.

In the most recent issue on "The Gear", Consumer Reports said
some very nice things about minidiscs in general.

In my mind the distinct advantage of DAT is that it records
16 bit digital sound at the standard sampling rate of 88.2 KHz
for a stereo signal. I find there to be three distinct
disadvantages. The first is that pieces can only be accessed
sequentially. One must wind and rewind to find a particular piece.
Secondly, there are lots of sensitive moving parts -- like a VCR,
DAT uses a helical-scanning rotating head. Thirdly, DAT seems
still to suffer from "drop-outs" which are more than an annoyance
to amateurs and professionals alike. I asked our professor
of electronic music just recently about the problem and he
confirmed that it is a continuing nightmare for people who
have to use DAT for a living.

The distinct advantage of minidiscs is that there is random
accessibility of pieces. Moreover, one can move tracks from
one place to another (I don't know why one would want to do
that, but Sony has built the feature into its systems).
I guess that editing of pieces can be accomplished very easily
with mixing and matching sonogram segments from two different
recordings of the same piece. I'm not the one to ask about this.
There is also alphanumeric labelling of all pieces. Minidisc
systems hold a 10-second buffer so as to be practically
immune (or so reports seem to indicate) to drop-outs.
There are two disadvantages. Minidiscs use "perceptual
encoding", a 5:1 compression which takes advantage of the
deficiencies of human hearing. Some people, such as the
author of the article I mentioned, claim that they can
hear the results of such encoding, and perhaps they can.
I'd feel much better about minidiscs if there were no
compression. Secondly, minidisc systems are VERY expensive
still. I've been watching the market for two years now,
ready abruptly to change my recording system at home (and
sound system in the car) as soon as prices become more
reasonable, but they have not yet begun to drop significantly.

As a result, minidisc systems have not yet gotten a foothold
in the market and they may never prevail because of the
possibility of Sony introducing a CD recording system (this
time supposedly compatible with commercial CD playback units)
in the next 6-8 months. The rumor also says that these CDs
will be erasable as well. The rumor has been around for
a long time and I'll believe it when I see the products on
the shelf of my favorite audio store.

Oliver