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Hello, Steve and Stevie, I have been using the MAM-A Gold DVDs since they came out and am pleased with them, but the last time I checked to answer Steve's question, MAM-A's attorneys are allowing them (or at least did allow them) to claim a 300 year life expectancy for the gold CD-Rs. The gold DVD-Rs I think have only been claimed at an 80-year life expectancy. The one thing, however, that I think we've learned from tape is that in highly complex chemical products, the anticipated failure modes and failure stimulii are not always the ones that will bring on end-of-life conditions. We have also seen how batch-to-batch variations in tape can affect the tape's longevity. Both of these lessons are instructive to the CD/DVD marketplace. For many of us, redundant RAID-5 or better arrays (i.e. two arrays in different locations), which can be managed and report errors seems to be a superior solution to more pieces of chemistry sitting on a shelf. Mixing one or more RAID arrays and LTO tape is also a good choice. I'm not really sure that, given the published life expectancy of the MAM-A gold media, that the media will be the first link in the chain to go. 80 years is pushing readability of "ancient" technology as complex as DVD and CD. However, that all depends on when the 5-inch optical disc drops out of the mainstream. It may be around for 60 more years, so in that case, the 80 year life is meaningful, but if it reaches end-of-life in 20 years, then keeping existing drives running for an additional 60 years will be problematic. Yes there are many pros and cons to each solution, but I see DVDs more as short-term storage of files for clients who will be developing a trusted digital repository in the foreseeable future. I prefer to send gold CD-Rs to clients who are unlikely to create a trusted digital repository in the foreseeable future. However, if the client has high fidelity material that can benefit from greater-than-CD-quality transfers, then we're stuck with gold DVDs, aren't we. CD delivery is the most costly, while downloaded files with MD5 hashes is the least costly and fastest, with individual hard drives being an alternate "envelope" for delivery of files. No easy solution, but nothing is permanent. Regards, Richard At 02:55 PM 2009-06-30, Stevie Duncan wrote: > We have done quite a lot of testing with many different types of DVD >stock and have found the MAM-A Gold Archival DVDs to be extremely reliable. >We have not done any specific testing as far as longevity, but the company >test info is here: >http://www.mam-a.com/technology/technical_papers/documents/longevity.html > >-----Original Message----- >From: Association for Recorded Sound Discussion List >[mailto:[log in to unmask]] On Behalf Of Steven Smolian > >Is there a reliable recordable DVD for long term storage, independently >tested? > >How does this compare with the anticipated lifespan of gold-reflective CDs? Richard L. Hess email: [log in to unmask] Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX Detailed contact information: http://www.richardhess.com/tape/contact.htm Quality tape transfers -- even from hard-to-play tapes.