I recently picked up a superb condition used copy of "A Study In Frustration - The Fletcher 
Henderson Story" 4LP set. I also have the new Mosaic Coleman Hawkins set. In the case of many 
overlapping tunes, the new set is clearly sourced from production shellac records whereas the old 
Columbia LP set is sourced from metal parts. To my ears, the Mosaic crew made some better EQ 
decisions for the new set, particularly in the low end, but their product suffers from distortion 
and surface noise of "well-loved" records that weren't quiet the day they were pressed.

So what happened to the Columbia metal parts? Or, why weren't the master tapes to "A Study In 
Frustration" used for the new set. If you took those old transfers from metal parts and applied the 
modern idea of EQ, using a good mastering equalizer, I think you'd get a better result because of so 
much less disk surface noise and pressed-in distortions from the shellac.

As of the early CD era, those original master tapes existed because Columbia put out the original 
"Study In Frustration" as a 3CD set in the 80s. I haven't heard those CDs, but my bet is that they 
suffer from the terrible overuse of CEDAR that plagued Columbia reissues in those days.

-- Tom Fine