I received my set yesterday. My CD ripping software conveniently found all the track titles. I already had most of the sessions, but agree the sound is nice (they did not apply too much noise reduction; there are some clicks/pops on a few tracks).
Last night I played the Buck Clayton July 1, 1954 session with Buddy Tate several times. Very nice! The recording itself is far from perfect, the tapes are 70 years old, but the Mosaic track sounds sharper, more vivid, than the digital version I had prior to that, which you can find on streaming services.
https://www.discogs.com/release/8976533-Buck-Clayton-The-Essential-Buck-Clayton
The liner notes describe how these Vanguard jazz recordings were first made:
"In Brooklyn's Masonic Temple, Seymour [Solomon] had found his ideal recording venue. With Hammond as his new ally, Seymour hung a single microphone 30 feet over the stage, and recorded the first Vanguard jazz session on December 29, 1953... The new series was called the Vanguard Jazz Showcase, and the initial recordings carried a balanced soundstage with the instruments surrounded by natural echo emanating from the room's wooden walls and floors."
These single microphone recordings required setting up the instruments correctly, and that was not always the case, as is explained in the liner notes:
"As is abundantly clear by now, there are plenty of benefits to the single-microphone recording system. However, one of its critical failures can be heard on the opening track of this session [Just a Groove]...one microphone cannot correct a faulty balance on stage! At the beginning of this track, it sounds like Buck Clayton (cup mute) and Ruby Braff (straight mute) are standing behind the rhythm section, and at times, the acoustic guitar of Steve Jordan nearly drowns out the trumpets! The piano was provided by the Steinway company, and while Hammond reportedly moved it to different spots on the stage before the session began, the placement of the instrument seems distant and unfocused on this track.... But if th'e microphne can't fix the balance issue, certainly the musicians can. After Jimmy Jone's mystical piano solo, the trumpeters ditch their mutes and move to the front of the stage. The increased clarity makes an enormous difference."