Hi Everyone,

The last time I commented on a physical archival issue I ran into a fairly
solid fundamental disagreement... regarding artificial ageing

I tend to base my numbers and facts on what I have experienced and learned
from many companies venturing into our field of work, and obviously what my
own company has had to deal with. I would do OUR (this list) communication a
injustice if I did otherwise.... I test all our materials very frequently,
and even if my company has only been in business for the last couple of
years, my professional audio experience spans a couple of decades.

Just to clarify some of my past opinions I would love to share an experience
I had today with one of our engineers (Heath).

We were asked to do an analog dub (some call it clone)... we quote the price
and move forward. Well...

We spend 4 hrs in the studio essentially rebuilding a Studer  827, trying to
find out why we can't print solid reference tones on track 3 (out of 24),
and without boring anyone with the details it turns out that the physical
analog media (a tape from the last run of GP9) had a slit error in the
physical coding process that revealed a "pumping" error in the flux levels
on this specific latitude of the tape...

We (this list) have several times talked about analog backup vs. digital,
but we still have to remember that the digital info has to go somewhere...
and due to cost concerns, most clients will go for LTO, AIT, etc.

Here is where I hit this thread...

Even if we trust the data tape we use we can get in trouble.... just to give
and example (I could have used PCM DAT tape).... We deal with ADAT mulitrack
tape all the time... from within the last 10 years... Essentially they took
a VCR transport and made it run faster... still recording 8 channels of PCM
audio on a regular SVHS tape. That, in it self, turned out to be a problem,
because any drop out will be across ALL 8 channels, due to the way they laid
out the data.

These machines were the beginning of the demise of the "professional"
studio. I would be the first to admit that the hourly prices in the
professional studios were way too high when these machines hit the street,
but AT LEAST the recording engineer and artist could be fairly certain that
the machines were aligned. I have experiences where a "rich" artist went to
ADAT because they could now build their own home studio for a reasonable
cost. It just so happens that they never spend money on a "tech" for the
studio... """ these new machines were flawless"""

Well the original recording machine is now in a dump heap somewhere, and
they were not aligned to ANY standard. In the archival world we now have to
"take a sledgehammer" to the playback machine to make the tapes play back...

At least we have auto aligning data machines when we deal with LTO's etc,
but it is not perfect...  getting an LTO tape from one studio to recover it
in another, often entails shipping the LTO drive with it.... the same goes
for Exabyte and AIT etc... this reminds me of shipping 2" quad video tapes
in the past, where we had to ship the head with the tape... remember that
the self aligning mechanism only works across about 40% of the possible
physical aligning area... centered around the physical placement of the

It's presently about getting the best odds possible... I store the LTO tape
drive with my tapes.... it's not perfect, but at least we have a chance, if
the client doesn't migrate 10 years from now.

I am not giving anyone the solution to a problem... I'm trying to convey a
mentality we all need to have... let's talk... let's learn from each
other... and no matter how invested we are in a single technology in our
practices or local studio, we have to understand that no solution is perfect
yet... more importantly we have to remember that it is OUR job in the
archival industry to make it work...

I hoping this email will give me (reveal) the perfect solution, but I'm not
holding my breath...

Sincerely with hope,


Claus Trelby
Managing Engineer/Partner

XEPA Digital
1137 Branchton Road, 19-N-3
Boyers, PA 16020-0137
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-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:[log in to unmask]]On Behalf Of Richard L. Hess
Sent: Thursday, June 09, 2005 9:32 PM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Longevity of data tape?--


As I know you're aware (I'm writing this to the others on the list, really,
not you), there is a huge difference between most of the "backup" tape
solutions that have been sold over the years and the enterprise-class tape
solutions like LTO. We definitely need clarification here.

However, as you are aware as well, the roadmap for LTO and AIT and S-AIT
make keeping a given format around much more than five years questionable,
I believe most of these formats will read back two generations and write
back one generation, but the space saving with a doubling of capacity per
generation makes you want to upgrade the library. The only downside of this
is it generates a lot of trash for the landfill and also costs some money,
but the upgrades are probably close to free compared to adding slots to the
robotic library system.



At 09:10 PM 6/9/2005, John Spencer wrote:
>were you using a specific software backup application, or using
>Windows generic backup utility, or a TAR archive?
>John Spencer
>On Jun 9, 2005, at 7:46 PM, Ken Hansen wrote:
>>I also would never trust DATA backup for longer than 5 years.
>>The past two places I worked I found this out the hard way.
>>Trying to restore 5 and 8 years old data respectively yielded horrible
>>We then implemented a policy to have all Data tapes checked and re
>>backed up to new AIT tapes with the understanding that those tapes
>>would then be checked in 5 years time.
>Richard L. Hess                           email: [log in to unmask]
>Media                           web:
>Aurora, Ontario, Canada             (905) 713 6733     1-877-TAPE-FIX

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