Hello, Steve,
Yes, my comment was about the 300+ year life expectancy that MAM-A is
forecasting for their premium gold-reflective-layer,
phthalocyanine-dye-layer "archival" CD-Rs.
I think they are forecasting 80-100 years on their gold-reflective-layer
DVD-Rs.
The work that Joe Iraci did for the Canadian Conservation Institute on
optical media longevity
http://www.uni-muenster.de/Forum-Bestandserhaltung/downloads/iraci.pdf
seems to point to the phthalocyanine dye as a major factor in his
testing. Gold has been identified as a major factor in other testing, I
believe.
But, as we knew back in the day, there were batch-specific tape issues
and these appear to be moving forward into today making some batches of
XXX tape more difficult to recover than others, we have Jerry Hartke
[log in to unmask] telling us that there are batch-specific issues with
optical media blanks of all manufacturers. He would like us to certify
optical media at the batch level.
And then there are the drive-media interface issues and stand-alone
drive issues. Sounds just like analog recording...oops, at the interface
level it is analog <smile>. Look at an eye pattern--that's an analog
phenomenon that is the basis of recognizing the digital information on a
wire or from a recorded medium. Here are two random links for eye-pattern.
http://www.audioquest.com/resource_tools/downloads/whitepapers/HDMI_eyepattern_BER_and_cliffeffect_rev_1_00.pdf
http://www.us.anritsu.com/downloads/files/11410-00462.pdf
Cheers,
Richard
On 2010-10-09 3:08 PM, Steven Smolian wrote:
> As to your last paragraph, I assume this refers to the gold-suraced CDs.
> Has anyone had actual faiures (other than those due to misues) on them?
>
> Steve Smolian
>
> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:[log in to unmask]] On Behalf Of Richard L. Hess
> Sent: Saturday, October 09, 2010 2:10 PM
> To: [log in to unmask]
> Subject: Re: [ARSCLIST] cassettes classical and otherwise
>
> There are many life expectancy issues with CDs, and I'm sure none of us will
> be around to sue MAM-A if we find their 300-year lifetime is erroneous based
> on some failure mode they did not test for.
>
--
Richard L. Hess email: [log in to unmask]
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.
|