I agree that zip'ing a file (or files - as in the case of a DDP file set) make the transfer more robust.
Strangely, when uploading Eric Benet's last master to Warner, they were very specific that if you uploaded zip'd DDP file sets, that they needed to be zipped with NO data compression. Apparently there is a way to do this, although I never investigated. In any case, they refused my zip'd (and data compressed) files (they compare file size pre and post extration to see if it was data compressed). Since I didn't want to take the time to figure out how to zip with no actual data compression, I just uploaded the DDP files as-is.... no zip'ing.
I received such a stern response form them in regards to this, I felt it necessary to investigate the matter, so I zip'd some DDP's, on both Macs and PCs, up-zip-ing on different computers and then re-importing into Wavelab... in each and ever instance I got the files to null.... I couldn't get then to not null.... so my impression of the data compression in a zip file is that it is solid.
I also upload to Discmakers a lot.... never a problem.
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