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Re: [ARSCLIST] Digital Audio Preservation Question
At 09:36 PM 2008-04-06, Tom Fine wrote:
I believe there is no good argument that lossy compression is ever a 
good idea with archival versions of things.
I totally agree on a general basis. For the Lonergan theology 
lectures that will eventually go up on T-Space, our workflow is this:
--We select the best copy (generally after transferring all copies)
--We then trim it and assemble it into individual lectures (which
   may not  match the breaks on the tapes)
--We infill pieces from an inferior copy which may be missing from 
the best copy
--We normalize the file
These are then saved as 44.1/16 WAV files (trust me, the original 
sources are FAR inferior to 44.1/16.
We then run all sorts of cleaning tools: generally a combination of
--Samplitude FFT filter
--Algorithmix Noise Free Pro
--Samplitude 4-band parametric EQ
--Samplitude Restoration Bundle De-Clicker/De-Crackler
   (don't ask me  how some tapes end up with ticks and pops)
These are saved as 128 kb/s MP3 files
The client wanted both preservation and access copies, didn't want to 
pay for two sets of WAV files, and didn't really want unprocessed 
copies, but when I got into it, and found out how bad the tapes are, 
we agreed to this.
IF we do advanced fixing, such as Plangent Process -- which I'm 
trying to get budget for -- then that output will be stored as a WAV 
as well. The one-minute demo makes a huge difference. In the case of 
the demo I put up for all to listen to, it's not perfect, but it 
makes it listenable.
There are all sorts of tradeoffs. In this case, the WAV files are 
estimated at 500 GB and the MP3 files at about 70 GB--probably +/- 30%.
Cheers,
Richard
Richard L. Hess                   email: richard@xxxxxxxxxxxxxxx
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.