Classical music series released on RCA Red Seal.
Any discs marked with the prefixes below refer to a disc from a set (all sets are in Mono):
- M [manual / 78-rpm / 10- or 12-inch]
- MO [manual / 78-rpm / 10- or 12-inch]
- AM [automatic / 78-rpm / 10- or 12-inch]
- DM [drop-automatic / 78-rpm / 10- or 12-inch]
- WDM [drop-automatic / 45-rpm EP / 7-inch]
- WMO [manual / 45-rpm EP / 7-inch]
The “Victor Musical Masterpiece” series began in 1926. This was not Victor’s first attempt at an album series. That honor belonged to the “Columbia Masterworks album series begun at the same time. Victor's albums had heavy cardboard covers and liner notes printed on each sleeve. Early in 1927, after the introduction of “Orthophonic” (electrical) recording, new albums appeared in paper or light cardboard albums, designated “Musical Masterpieces on Victor Records.” Again, these didn’t carry set numbers. Approximately the first fourteen of what became the M- sets were issued in this series. In mid-1927 the packaging changed to the heavy cardboard covers with set numbers shown on the spine, and the M- series was born.
78-rpm shellac records from 1927-1951 use catalog numbers M-1 to DM-1523. (AM and DM- catalog numbers were used for automatic sequenced records that were auto-coupled for continuous playback, but in different sequences. AM = 1/6 2/7 3/8 4/9 5/10; DM = 1/10 2/9 3/8 4/7 5/6. One theory is that the AM sequence allowed radio play with two turntables, that allowed the next side to be queued without stopping to flip the just-played disc.) From 1951 onwards, the series, except for a few (mostly South American) issues, switched to 45-rpm only issues. The catalog numbers span from WDM-1524 to DM-1667. At this point, the catalog numbers jump up to 1700 and the WDM- (45 rpm ) and LM- (LP) numbers are interchangeable. These simultaneous issues continued until about 1770, at which point most titles were issued in LP format only.
The 45 sets from WDM-1705 up all contained four records (EP’s). Among the other series introduced at this time: LM/WDM-6000's (2 LP’s or more); LM/WDM-7000's (10" LP’s - the corresponding 45 sets contained three records); LHMV/WHMV (reissues of HMV recordings in a special series).
After RCA began issuing only selected titles as 45 rpm sets, the prefix on those sets was changed from WDM- to ERx-, where (x) represents the number of records in the set. (ERA- for one record, ERB- for two, ERC- for three, etc.) Those sets with three or more records had the same number as the corresponding LP issue, but the ERA’s were a separate series starting from ERA-1 (and some of the ERB’s also, though some seem to have corresponded to 10" LP’s in the 7000 series, until these were discontinued). Popular EP titles were prefixed EPA-, EPB-, etc. Thus “E” in this prefix represents “Extended Play”, “R” represents “Red Seal”, and “P” represents “Popular”.
The LM- numbers were continued into the “Living Stereo” era as LSC- issues with the same numbers. This series was only supplanted in the early 1970's by a new series (ARL1- for Red Seal single LP issues). The LSC- series had reached well into the 3000's by this time. The last of their line can be seen as a direct continuation of the earliest Victor 78 rpm sets of almost 50 years earlier. This fact is reinforced by the last 78-rpm DM- set issued, the only 78 issue above 1700: “Christmas Hymns and Carols, Vol. 2" (Robert Shaw Chorale). This was issued in all three speeds: LM/WDM/DM-1711!
