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Although the Red Book CD-DA has two levels of error correction using a
cross-interleave Reed-Solomon code, an additional safeguard against
degradation is available using CD-ROM Mode 1. This format adds a
powerful, third level of error correction using a Reed-Solomon product
code. (This third level is not available in CD-ROM Mode 2.)

Although use of Mode 1 requires conversion of audio to WAV or other
formats in order to obtain files, the additional effort should be
mandatory for archival purposes. In addition, use ISO 9660 Level 1
volume and file structure, and disc-at-once recording. These options
should be selectable in any professional grade recording software
programs.

Of course, media and recording drive quality are also very important.

Jerry
Media Sciences, Inc.

Richard L. Hess wrote:
>
> Chris,
>
> "permanent digital archive" is a shorthand for a managed archive. Sorry, I
> should have been more specific. Permanence is acheived by migration when
> necessary.
>
> When I refer to this, I refer to files in a managed, long-term storage
> situation. Some third-party suppliers are starting to provide this as a
> service.
>
> I doubt we'll have much trouble reading WAV files in 100 years. They may be
> laughed at, but it won't be a problem, I suspect.
>
> Also, when I was referring to CDs, I was referring to red book audio CDs.
> That is the pervasive, common denominator.
>
> I'm seeing archives of oral history waste away--I'm managing to personally
> help salvage two--I wonder how many more are out there.
>
> One of them had the funding to also transfer to reel (38 hours) and I am
> doing that. The other, with a worse problem, is struggling. They have 3000
> hours.
>
> I see how hard it is for many people today to get good playback from analog
> tapes. Yes, someone like you and me will be around in 100 years to struggle
> through playing analog tapes, but it won't be the norm, and it won't be
> worth the cost in many instances.
>
> Perhaps my view is skewed, but many of the archives worth saving are, at
> the best, good cassette quality. Certainly there are some recordings which
> deserve more than red book CD, but many of the archives out there that
> provide a snapshot of our world--our voices, our sounds, our thoughts, our
> inflections--are seriously not even Nakamichi cassette quality.
>
> We're not talking Metropolitan Opera or Chicago Symphony for most of these
> archives, but the cultural significance is no less important.
>
> Perhaps people will want to transfer red book CDs into a permanent digital
> archive or some other storage medium in 25-50 years and that is fine. I
> don't think the 3,000 tape archive would be around then.
>
> By the way, to put this in perspective. The record machines for the vast
> bulk of the 3,000 reels were Wollensaks at 3.75 in/s. Please, will someone
> tell me how this audio quality will be hurt at 44.1ks/s, 16 bit? We're
> playing these 3,000 tapes on a Studer A807 and recording them onto two Sony
> CDR-W33s.
>
> Yes, there is a broad spectrum, but with the generational loss of analog
> recordings, we can't go too many generations without serious degradation.
> Capturing the sound to digital freezes the losses now.
>
> With the challenges of getting good people to play analog tapes, I cannot
> imagine the challenges of getting them to record them as well as possible.
> I know some very good analog tape people. I don't see many around.
>
> I'm not advocating destruction of master reels. If a better
> playback/encoding scheme is around in the future, the transfers can be done
> then.
>
> I see overlapping curves as analog reproduction quality falls and digital
> capture quality increases. The trick is to pick a time where the analog
> reproduction quality hasn't fallen substantially and the digital capture is
> starting to plateau out.
>
> I think you're aware of a major west coast archive on a fishing expedition
> to see how much it would cost to transfer 4000 or so assets to files. In
> fact, in your day job, I suspect you bid on it, and I wish you well. They
> were not requesting analog safeties as I recall it. I think their head is
> in the right place.
>
> As I said it's my opinion. You certainly are entitled to yours. I hope
> we're not getting into an analog/digital debate, but to me the path is so
> clear for the vast majority of archives...but in case I'm wrong, keep the
> original reel masters, too.
>
> Cheers,
>
> Richard
>
> At 12:33 AM 6/26/2003 -0400, chris2 wrote:
> >Richard,
> >
> >First, I have to say that I have no interest in arguing analog vs.
> >digital at all, and that is not my intention here. The issue is too
> >complex to be so black and white. Criteria for proper choice of format
> >should be dictated by the
> >ability to meet preservation goals and objectives of the collection or
> >institution. Having said that I have to say that I disagree with your
> >statement. Use of the term "Permanent digital collection" is a bit
> >misleading. Where does the assumption of permanence come from? Digital
> >archives need an infrastructure to support them and proper maintenance
> >and upkeep. Not every institution has the hardware or IT knowledge to
> >support a digital archive. Sure, you may not need an IT department, but
> >you need, at very least, easy access to someone with significant
> >understanding and working knowledge of IT and digital file storage and
> >access. Maybe hard drives are getting cheap, but digital preservation
> >does not consist of finding the cheapest hard drive available to store
> >files on. What about initial and ongoing media and data integrity
> >checks? These are not things to take lightly and not things that a cheap
> >terabyte drive offers. What about metadata specifications, storage and
> >access? What about a migration plan? There has to be policies and
> >guidelines in place. Yes, digital archives are a current possibility and
> >are actual reality at this point, but they are only an appropriate
> >choice if you have the right people, knowledge and systems in place. It
> >is certainly too harsh and simplistic to say that someone who chooses
> >open reel tape is being "Financially irresponsible".
> >In regard to access in 100 years, based on the playback mechanism, I'll
> >take the open reel deck in a bet. If you can wrap wire around a chunk of
> >iron and move the tape at a constant speed you can get the data off and
> >recover something useful from tape. Simple mechanisms and systems that
> >can be easily reconstructed beat complex ones.
> >The chances of being able to build a machine from scratch in 100 years
> >that can play analog tape is much greater than being able to build a
> >computer, operating system and drive mechanism that can access a CD and
> >then play back the file format stored on the CD. If obsolescence is an
> >issue in the analog domain, it's a crisis in the digital domain. Look at
> >the rapid changing of technology in the digital domain just over the
> >past years. How much data do you think has been lost and is stranded on
> >obsolete computers, operating systems and media? There may be more CD
> >players than open reel decks that have entered into the market, but that
> >is only part of the equation. After you have a drive mechanism, computer
> >and operating system there are many more complexities. First, are we
> >talking about a data CD or audio CD? If it's a data CD, how is it
> >formatted and what is the file system? Is it a CD-R or CD-RW? 650 MB or
> >700 MB? What is the file format of the data on the CD? What is the bit
> >stream encoding method, sample rate and bit depth? Is there a container
> >or wrapper involved? Is the metadata stored internally or externally and
> >in what format? How many CDs is the data split over and what is the
> >consistency of metadata between them.
> >I really say all this to demonstrate the inherent complexities in
> >digital storage, and this is only scratching the surface. My description
> >of tape is also an oversimplification to some extent, but I'm just
> >trying to make a point. Truly, chances are that future archivists and
> >librarians will be confronted with a lot of WAVE and PCM data and will
> >be able to fairly easily interpret this data. This implies many things
> >though that can not easily be glossed over. Also, while Jerome Hartke
> >gives good input on CDs, CD may not truly present the best option to
> >many institutions and can not so easily be given credit as the best
> >stopgap before digital archives are available to the "average archive".
> >Depending on the goals and objectives (preservation, interim storage
> >medium, access) there may be other viable options beside CD. The
> >decision of preservation/destination formats is a big one and worthy of
> >careful consideration, particularly for larger collections. There is no
> >right or wrong answer at this stage in the game. It's not about if a
> >Macintosh or PC is better. It's about which tool is right for the job.
> >That's my .02.
> >
> >Chris Lacinak
> >
> >-----Original Message-----
> >From: Association for Recorded Sound Discussion List
> >[mailto:[log in to unmask]] On Behalf Of Richard L. Hess
> >Sent: Wednesday, June 25, 2003 5:47 PM
> >To: [log in to unmask]
> >Subject: Re: [ARSCLIST] Long-term/preservation audio
> >
> >
> >Hi, Lance,
> >
> >Since the quality of reel-to-reel playback is very machine and
> >technician dependent I have serious doubts about the playability at
> >highest quality of an analog magnetic tape in 100 years time.
> >
> >By then, the technology will be stone-age. Nobody will be around to
> >understand it. No one will care. It's dead technology now. It started
> >dying in the 1980s with Ampex leaving the business. Studer is now
> >essentially out of the tape recorder business.
> >
> >What will happen when people like Jay McKnight of Magnetic Reference Lab
> >no longer make test tapes?
> >
> >Can we even buy good blank tape today? For how long? Quantegy and Emtec
> >are still in business--the latter is or was in a bankruptcy-type
> >restructuring as I understand it.
> >
> >Few highest-quality recorders are available new today and those that are
> >are end-of-life products being kept in production for archival
> >migration. The Otari MTR-15 is a special order product but the MX5050
> >BIII is apparently available from stock. Studer is currently NOT listing
> >the A807 on their Web sites and did a "last call" for this machine two
> >years ago.
> >
> >I personally feel it is financially irresponsible and a waste of scarce
> >capital to fund transfers to reel tape today. The money spent doing this
> >could be better spent transferring to a permanent digital archive.
> >
> >The use of CDs is the best stopgap we have before permanent digital
> >archives become pervasive, affordable, and robust for the average
> >archive user (i.e. not requiring a dedicated IT department). CD players
> >because of their huge penetration--more by far than reel tapes ever
> >were, I suspect--will be around for years to come.
> >
> >These are my opinions only.
> >
> >Cheers,
> >
> >Richard
> >
> >At 04:41 PM 6/25/2003 -0400, Watsky, Lance wrote:
> > >The question actually posted specifically asked about long term
> > >preservation. The problem is not whether or not CD's and DVD's will
> > >last for posterity, but if the players will still be around in the
> > >future. Although digital and optical media is wonderful for providing
> > >access, I believe that the Library of Congress still promotes utilizing
> >
> > >reel-to-reels to serve as their preservation copies. Can someone please
> >
> > >correct me, if I am wrong.