Abbreviations for sound quality are listed below. Sound quality is subjective. Collectors understand that we are fortunate to have these performances in the best sound possible, and it can range from Mapleson sound to near commercial quality. Early performances in particular have age-related defects, especially if they were recorded from home acetates or primitive recorders. In-house recording equipment was generally poor until the late 1960's, with scattered acceptable results depending on seat location, or availability of the house wire.

NC ? Nearly Complete
Original Transcription -- First generation copy from 16" disc or source acetates
Exc. -- Top quality with few or no defects in sound
Vg-exc. -- Still fine quality, but with very minor defects, or none at all.
Vg -- Acceptable sound, but age-related defects. Voices forward.
Gd-vg -- Lowest level of acceptance, but still an important file copy.
Fair -- Barely acceptable. Requires concentration and tolerance.
Poor -- Only a file copy until something listenable comes along, if ever.
IH -- In-House tape. The acceptable ones are exc. Or vg. Lower than 
these are a chore to listen to, and are only file copies.
(S) -- Live performances in studio productions
No sound quality listed -- Copies available, but unheard. If interested, 
contact me. Range is fair to vg.
TRADING-- I am interested in upgrading my poor, fair, and good performances to the Level of vg-exc. Or excellent. For other cast information, if available, contact me.

In order to preserve the integrity of the Microsoft Database (Access), dates are handled as follows: 
Only the year was known ?C the date is listed as 1/1/year. Only the month and year known ?C month/1/year. (This will handle everything, except for actual performances on Jan. 1st., etc.)