I had a lot of experience mastering to this format a while back. I can echo the sentiments of Tom Fine and the others. While it could be a very robust format when it worked properly, there were SO many variables that could go wrong, you never knew if you had a good, finished master tape until the very end of a real-time transfer. I'm not sorry to see it die as an audio format. Cloning one 1630 tape to another using a DAE-3000 editor was akin writing your 50-page research paper on a manual typewriter.
My setup was: (2) U-matic decks, a 1630 processor with all the right cards installed, the DAE-3000 editor and its 4U(!) rack space processor to go with it, a small b/w video monitor to make sure you were actually recording something to the tape, a Sony Digital Tape Analyzer to monitor the record machine as it ran, and counted the uncorrectable CRC errors, overs, mutes, etc. that would render your tape useless, and a printer to print those results.
Unfortunately, the major label archives have many hundreds of thousands of one-of-a-kind digital masters still on this format (and nowhere else) that it's going to become an archiving nightmare very soon. Sony wants to pretty much forget it ever made the 1630, so they won't support it anymore. Hopefully, someone can take up the cause...
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