Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!wuarchive!rice!hsdndev!bbn.com!nic!hri!sparc26!mull
From: mull@sparc26.hri.com (Chris Mullendore)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Diffs between DD & HD disks (#2)
Keywords: DD HD
Message-ID: <1991Apr18.215253.27949@hri.com>
Date: 18 Apr 91 21:52:53 GMT
Sender: news@hri.com (News Admin)
Reply-To: mull@hri.com
Organization: Horizon Research, Inc.
Lines: 30

I'm sorry if this has already been dealt with, but I joined this
discussion late.

I'd like to pose what I think is a slightly different question.  It is
rumored that a reputable company like Sony no longer makes the older DD
media and only makes the HD media because it is cheaper for them to do
so.  As a result, all new Sony DD disks actually use HD media but are
tested for DD use, the rumor goes.  Now, of course, if this is true,
Sony would never admit it nor would any other manufacturer doing the
same thing.

There is a precedent for this kind of behavior, however.  We all know by
now that 8MM data certified tape is nothing more than Sony 8MM metal
particle video tape, repackaged, data certified, and sold for a lot more
money.  But the cat's out of the bag and everyone I know does system
backups with Sony 8MM MP video tape, and like us, do there own data
certification if any.  Personally, I don't believe data certification is
necessary given Sony's quality control and we have not had one problem
with the numerous restores that we have done over the years with this practice.

I recently bought some Sony DDs and HDs so I could do some comparisons. 
The HDs were manufactured in the USA, while the DDs were manufactured in
Mexico with Japanese and US parts.  Doesn't really support the rumor, does it?

So I think the issue for me is if Sony DDs are actually Sony HDs, then
why should I waste money to buy the HDs?  I admit the tough part is
getting a confirmation of the rumor.

Chris Mullendore
mull@hri.com