The Ongoing, DDS versus Audio DAT, Debate
This debate comes up at least every 6 months, or so, on DAT-Heads
and other forums. A couple of years ago I assembled some info
that still holds true today. So please read on...
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I have to preface this with a few comments.
I do have a vested interest, but as a nimble retailer I would only
sell audio grade DAT if I could be convinced that audio grade is really
a better tape and the market demanded it. I do believe, though, that DDS
is a higher quality tape. This is based on my 8 years of selling hundreds
thousands of them to radio stations, recording studios, universities,
thousands of DAT-Heads and using them myself.
I also have over 30 years experience in the recording industry and own
2 audio machines, a Panasonic 3700 and Sony 75ES. I also have 2 Wang
DDS data drives.
When I first started selling this tape I was informed through various
reps that the tape was different. According to them DDS tape was easier
on the heads and would run cleaner. In fact, according to my contact
at WangDAT, Matsushita (check my spelling), a major DAT mechanism
manufacturer, would even warranty their heads longer *if* DDS tape
was used.
Within the last couple of years I had come to believe that DDS and audio
grade tape were the same. I learned of this from A Fuji engineer and rep
and also from a Maxell tech bulletin that the DDS tape was taken from
the *center of the roll.* It is certified error free but still comes
from the SAME ROLL AS AUDIO GRADE TAPE. At least, in retrospect, that
must be the case with Fuji and Maxell. Of course that would not be the
case for 90 meter as it is a thinner tape and doesn't exist in audio
DAT tape (though some have reported seeing a 180 minute audio DAT tape).
It seems that the truth lies somewhere in between, that each company
has their own techniques for manufacturing DDS tape.
A rep at DIC digital informed me that the back coating on their tape is
different than their audio grade. According to him, one of the biggest
problems of DAT tape is that the back coat "shatters" causing shedding.
The back coating on their computer grade tape allows the tape to run
smoother and helps prevent this "shattering" effect. And of course
they certify them error free.
Here are some response to some of Doug Oades previous comments on this
subject:
>Hello !! I looked on the back of various tapes to get phone
>numbers. I talked to sony , maxell , tdk & kao , sony says the
>dds tape is different, the shells are interchangable , but the
>tape is not. kao does not make audio grade tape. maxell says
>the tape is different, It's been my experience that, depending on who you talk to at any
given company, you can get a different story every time!
BTW if KAO says they do not make an audio grade tape then why is
APOGEE having KAO make their tape?
>Michelle from TDK called me today to
>tell me that an internal memo states that the tape is the same
>only the shell is different.
Then what about those folks who say they have problems with TDK DDS
but *not* TDK audio grade? Same tape? I just talked to a customer who
sent some DDS tape back to TDK after they supposedly admitted to him
that it was a different tape than there audio grade! Like I said
it depends on who you talk to!
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Now, here are some comments from some satisfied users from the last
go-around in this controversy and hope they don't mind me re-posting
their comments.
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From: "Brendan P. O'Neill "
Subject: DDS vs. Audio grade 4mm DATs
Date: Thu, 23 Nov 1995 15:53:22 -0800
It's been some time since I've postedhere, been lurking/reading for
over a year now, and I'd like to add my 2 cents regarding the DDS vs.
Audio grade DAT debate.
I mix sound for a band that plays out over 200 nights a year, and I
record every night on my DA-P20. I always use 90 meter DDS tapes, and I
have had, maybe, 5 or 6 tapes do funky things on me at various times. I
also have had a great deal of experience using audio grade DATs in the
same machine and other machines as well, with about the same rate of
problems occuring with audio DATs as do with the DDS tapes.
I am not qualified , by any means, to argue specs. I use the 90 meter
DDS tapes all the time, and am very opleased with the results. I have
had several tapers jump at me for using and promoting th euse of DDS
tapes, with some schpeal about sheading and streatching and all that
other BS. I have, on many ocasions, checked error rates on 3700's and
th elike, and always came up with results well withen workable limits.
As a matter of fact, over th eholidays I will be backing up my
collection of DATs with clones, and plan to use 90 meter DDS tape s for
every one !!
If there is some scientific proof, some 100% unquestionable reason for
me not to use DDS tapes, please bring it to my attention.
back to lurking !!!
Brendan
audio engineer/road mgr. moe.
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From: Bryan Levin
Subject: Re: dds vs. audio grade (addition to my original post)
Date: Mon, 27 Nov 1995 09:15:01 -0800 (PST)
Jason Kreuter writes
:
>
>SOme
people believe that DDS is fine, others believe the DDS does shred
>(as my repair guy - WHO WAS NOT A SONY repair person but was authorized
>firmly believes). Most people defending the DDS said it was only
>TDK DDS that shreds in the transports...
Lets clear up a misconception that seems to be cluttering dat-heads of late:
DDS (digital data storage) tapes do _NOT_ imply 90 meter lengths.
While manytimes, DDS tapes are sold in 90meter or longer length, there are
plenty of 60meter (120minute) DDS tapes that are simply wonderful.
Very low error rates, good shells, etc.
Folks, there is no reason to slam DDS tapes, in general. Talk about
_LENGTHS_ or specific brands (TDK, perhaps) but not the mere fact that they
were spec'd out as DDS.
The length is what affects the tension; incorrect tension affects trackability,
which causes noise and dropouts.
Of course, problems do occur when oxide 'sheds' off the tape and onto your
heads, but there is NOTHING inherent in the DDS spec that makes DDS-grade
tapes shed more than audio-grade. Again, look to the brand - there are good
and bad implementations of the DDS spec (and audio spec, too!)
So, please, be more specific/correct in your complaints about tapes.
As Art M. and Steve S. have said (and others, as well), DDS, by itself, is
nothing to fear or worry about.
nuff said,
--
.bl
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From: "Alexander W. Chin"
Subject: DDS-2 Tapes in a D7
Date: Wed, 29 Nov 1995 01:58:53 +1100 (EST)
Hi,
I have myself a Sony TCD-D7. I have to admit when I bought it, I didn't
know about DDS-2 and DAT tapes. Anyways, when I got it, I didn't have a
blank tape to play with it. So I borrowed one from my office. It happened
to be a DDS-2 120 m tape. I thought the 120 m was the same as the audio
grade 120 minute tape, so I chucked it in and recorded to my heart's
content. Imagine my surprise when I found out that it was good for 4
hours on SP and 8 on LP.
To cut a long story short, I went out and bought one. Have been using the
tape for more than a month, with a lot of heavy use, fast forward and
rewind to listen to a particular song I recorded. so far no problems, and
I even took the D7 and the tape apart to see if there was any
damage/stress and the like. Not a thing. So, I guess that DDS-2 tapes are
OK to use (on a D7 that is).
The only problem I have is that the D7 gets confused when it reaches the
middle of the tape during fast wind. It thinks that the 120 min tape is
near the end and slows down. That makes winding that tape painfully slow
if you go from one extreme to the other.
Also, would anyone happen to know what happens when I do a digital copy
of a CD. Does the recording head speed get locked to the incoming data
rate or is it set by a local crystal, and the incoming data resampled (in
the case of very slight difference in clock speeds).
Any ideas?
Also, the D7 is a very nice machine - I like it.
Alex
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Return-Path: ch
X-Sender: cvg2@miles.netpoint.net (Unverified)
Date: Fri, 1 Dec 1995 09:39:45 -0500
To: artmuns@tape.com
From: cvg2@netpoint.net (Computer Video & Graphics 2)
Subject: DDS saga
Right On Bro.........
I've used about 300 90M DDS tapes of many brands.
I've had mabe 2-3 bum tapes.
I prefer 90M DDS tapes because of their length.
Thanks for the good service.. Art
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From: Gary Davis
Subject: 90m DAT's: my results
Date: Sun, 24 Dec 1995 01:38:18 +0000
I have used almost exclusively 90m WangDATs from cassette house.
I've used them in Sony's D3, D7, D8, A8, Foxtex D-10 and Tascam
DA-60. In the Sony's I've done a lot of 6 hour recording (easily 6
or 7 shows that were continuous 6 hours).
I've had no problems at all.
Frankly, I think it's the responsibility of the manufacturers to make
the machines work with 90m tapes, knowing they are widely used in the
field. I think they're just hedging their bets, and maybe trying to
get out of those extended warantees....
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Return-Path: Hans.Albertsson@Sweden.Sun.COM
Date: Wed, 6 Dec 1995 15:56:34 +0100
From: Hans.Albertsson@Sweden.Sun.COM (Hans J. Albertsson - Sun Sweden)
To: artmuns@tape.com
Subject: Re: DDS update III
X-Sun-Charset: US-ASCII
I called the local Swedish 3M people, and they were adamant about the
following:
Yes, DDS and DAT are different: DDS is a finer particle mix, better
polish, and slightly stronger backing and binder, to compensate
for the thinness of the longer variety.
Local Stockholm sound studios that do regularly buy 3M DAT tapes have
switched to 3M DDS 90m and 60m from 3M DAT, and are seeing MUCH lower
error rates and wear for their pro gear and portable Sonys alike. And
they wondered why I was worried!
They did NOT, however, volounteer any sound studio names. Because of this,
I will refrain from drawing any conclusions.
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From: Computer Video & Graphics 2
Subject: Re: What's the length of life of DAT head & tape ?
Date: Tue, 26 Dec 1995 09:17:31 -0500
I've played a particular DAT going to sleep every night for about 3 years
and it always works like a champ. Mabe 1000 + times.............
Do I hold the record?
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From: Sascha Dungs
Subject: Re: more sv255 questions
Date: 10 Mar 1996 13:01:33 +0100
> This seems true. I had 2 identical Sony decks which had the same
number of
hours on each. One of them never saw a DDS tape while the other saw both.
The DDS deck was always in the shop. In fact, the Sony center asked
if I
was using DDS tapes! Note that my DDS tapes were almost exclusively
60's.
When I was using my Sony-DTC 690, I also did buy only
audio-grade (Denon) tapes. It was always in the shop anyways...
A firend of mine did also use only audio-grades and he had about
5 different Sony-decks after another which were repaired 3 times
each...then I bought a Pioneer D-500 and he bought a Technics SV
DA10. Now we`ve been using only DDS-tapes (I`ve got about 150 tapes
of which 110 are DDS, he`s got about 175 tapes of which about
100 are DDS) for about 1.5 years and had not a single problem. I
guess my Pioneer must have been running for about 3000 hours
with DDS tapes.
> I spoke to Jim Oade (who just had a baby, congratulations) a few weeks ago
and he said that they see a ton of decks coming in because of DDS tapes.
I believe that Sony gets tons of decks back. I really *don`t*
believe it`s because of DDS tape usage.
I hope my English is quite understandable.
Regards,
Sascha
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From: Tom Rumland
Subject: Re: to dds or not to dds
Date: Sun, 10 Mar 1996 22:03:37 -0500
>the problem i see with dds is the denser oxide on the tape to achieve 100%
error free status.
this oxide will dirty up your heads faster. if you use this stuff, i would
>learn how to manually clean your heads, and do it twice as often. when i
>say manually, i mean popping the top and using ozone depleting solvents on
>a caimois swab,directly cleaning the head; not a dry cleaning tape.
>[deletia]
>
>common sense tells me that on my 3700, i can record (or play) 20 audio
>grades (sony) before error counts dictate a
>cleaning. on dds, anywhere from 5-10, depending on the tape. dic dds seemed
>to be the worse.
>
michael,
i think the problem you are having is not with DDS itself but with the
brand of tape you are using. i have a 3700 myself and have been using
nothing but DDS. i usually only have to clean the heads after about 40-50
tapes. i did buy a batch of sony blanks and that required much more
frequent cleaning (and un-jamming). the other day i used a sony DDS blank
to back up a workstation and dump hated the tape (said it had to wrote the
data 14 times before it was able to verify the write properly). i
immediately cleaned it and tried it with a Fuji DDS blank and then a maxell
DDS blank...both went flawlessly. i then tried the sony again to make sure
that it wasn't that i had dirty heads to begin with. the choked once again.
========================================================================
Tom Rumland | Strange Brew Inc. | trumland@access.digex.net
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Home Page: http://access.digex.net/~trumland
DAT List: http://access.digex.net/~trumland/digital.html
Want List: http://access.digex.net/~trumland/wantlist.txt
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Needless to say this is a debate that will probably never go away.
Art
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