The question, then, is:
When not choosing 24-bit, should we use UV-16 during the record process? (Straight 16-bit sounds so atrocious comparatively, I wonder if it’s better for you that we send a pre-dithered recording and let you re-dither on the output after you’ve done the fades and edits?)
The goal is to stay if possible with 24 bit source and one final dithered pass to 16. Find a way to send us a source as close to the original mix as possible, that has not passed through multiple passes of 16-bit dither.
If you send me a 16-bit source and I don’t have to process it to make it sound good, other than editing and fades…. Sonic Solutions can turn its dither on and off automatically (as can some external dithering processors) so if I’m forced to reprocess material that is already dithered, only the sections that have to be changed will be affected, the rest remain perfect clones. But most mastering involves processing (equalization, dynamics processing, etc.) to produce a product, and thus, I will be forced to redither at the end. This puts us in the position of putting dither on top of your dither. The sound can go downhill… it’s a tradeoff between the high quality processing we do and your original source.
The two most damaging steps in the digital recording process are the A to D conversion and the dithering. They both seriously deteriorate the source material, at least with the state of the art of technology today. Dithering is a necessary evil. Without it, you get distortion. With it, you get noise. You asked about UV-22. Personally (and this is my opinion), I am against use of either the normal or “gentle” form of UV-16 during the record process when forced to record 16 bit. In my experience there are other, more transparent dithering methods, especially if you are going to be dithering again. I would prefer to leave the choice of UV especially to the end, because to my experience it does add a veil, often a very pleasant veil, often a very “neutral” veil….but I’d hate to use this type of veiling in intermediate stages of processing. If you’re positive you will not be doing further eq or level shifting or other processing (such a rare case, really), then of course, dither to 16 bits at the beginning, and occasional crossfades with or without additional dither will probably be insignificant to the product. However, there are now relatively inexpensive methods of recording 24-bits.