Re: [ARSCLIST] Fw: [ARSCLIST] Gold CDs

[Jerome Hartke <jhartke@xxxxxxxxxxxx>]

CD error correction is contained on the disc, and is defined by the
standards. Drives can ignore some of these capabilities, as happened with
early high speed drives. Or feedforward techniques can enhance somewhat the
maximum defect size, as is done in most modern drives. "New" systems are not
allowed if the disc is to be a CD.

It seems rather fruitless to characterize drives model-by-model. The key is
to initially record high quality discs, and to periodically test samples to
detect degradation while the disc is still readable and a copy can be made.

Jerry
Media Sciences, Inc.

> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:ARSCLIST@xxxxxxx] On Behalf Of Steven Smolian
> Sent: Saturday, November 06, 2004 10:14 AM
> To: ARSCLIST@xxxxxxxxxxxx
> Subject: Re: [ARSCLIST] Fw: [ARSCLIST] Gold CDs
>
> Hi, Peter,
>
> It seems to me the expressions need to reflect (wrong word?) the degree of
> assumed average longevity.
>
> Longevity is playback using the error correction system of the day, which
> means the chip has to be identified.  There need to be a list of CD
> players
> grouped by error correction systems, contunually updated.
>
> New and better(?) error correction systems should be identified as they
> appear and players using them should be reviewed.  A standard test disc
> should be created with a variety of errors and run through successive
> playback machines, toward the idea that, with these problems, it won't
> playback on this one but will on that one.
>
> Of course, test figures with no error correction system in place heads the
> list.
>
> Average longevity assumes proper storage and might be expressed in dd's,
> death dates, as in 40 years plus or minus 5 years.  Some PR guy can come
> up
> with a more genteel way of expressing this.
>
> Assumed average longevity.  Assumed implies that this number is an
> extrapolation rather than a figure arrived at by waiting 40 years.  It
> supplies cover in the event of CD sticky shed.
>
> Any test results must take into account the various methods of labeling as
> well as the disc surface type, each combination treated separately.
> Otherwise, results will be unrelated to real-world uses.
>
> Steve Smolian
>
>
> ----- Original Message -----
> From: "Peter@xxxxxxxxxxxxx" <lists@xxxxxxxxxxxxx>
> To: <ARSCLIST@xxxxxxxxxxxx>
> Sent: Friday, September 24, 2004 1:41 PM
> Subject: Re: [ARSCLIST] Fw: [ARSCLIST] Gold CDs
>
>
> >> -----Original Message-----
> >> From: Association for Recorded Sound Discussion List
> >> [mailto:ARSCLIST@xxxxxxx]On Behalf Of Joe_Iraci@xxxxxxxxx
> >> Sent: Friday, September 24, 2004 1:54 PM
> >> To: ARSCLIST@xxxxxxxxxxxx
> >> Subject: [ARSCLIST] Fw: [ARSCLIST] Gold CDs
> >>
> >>
> >> "... and, most significantly, on storage and handling."
> >>
> >> Storage and handling, of course are major elements in any longevity
> >> discussion.
> >>
> >> "For example, if there were standards by which the term "archival" was
> >> defined and enforced,
> >> then one or more lines of blanks labelled "archival" could be used."
> >>
> >> Archival is a tricky word and can mean different things to different
> >> people.
> >> Joe
> >
> >
> > NIST just put a good document on storage and handling and the AES/ISO
> > Joint
> > Technical Commission is currently working on a Optical Disc storage and
> > handling document.
> >
> > As far as "archival" is concerned, on the Joint Commission, we've been
> > trying to do something about putting a reasonable definition in the
> "Terms
> > and Definitions" section of a number of AES, ANSI and ISO standards
> > documents for years.  Unfortunately, the response we've gotten has not
> > been
> > promising.  Trying to define "archival" at this point impacts too many
> > previously published documents and , frankly, has too many political
> > ramifications in the industry for a "formal" definition to pass the
> > standards voting process any time in the near future.  This is why we
> have
> > had to make do with phrases such as "medium-term life expectancy" and
> > "extended-term life expectancy".  You might notice that these phrases
> > don't
> > seem to have been picked up in advertising literature.  Oh well, a
> > consensus
> > on what archival means when referring to media would be really nice and
> > I'm
> > certainly open to any suggestions on how we all could get such a
> > definition
> > into a published standard.  Any ideas?
> >
> >
> > Peter Brothers
> > President
> > SPECS BROS., LLC
> > (201) 440-6589
> > www.specsbros.com
> >
> > Restoration and Disaster Recovery Service Since 1983
> >