PMCD

PMCD (PreMaster CD) is a specially formatted, recordable Compact Disc designed to be sent to a CD pressing plant for replication. The PreMaster CD format, developed in the early 1990s by the CD-ROM division of Sony, in cooperation with "START Lab Inc." of Tokyo and Sonic Solutions, contained a hidden "PreMaster Cue Sheet" that held the metadata needed for replication that a Red Book CD-DA lacks. The PreMaster CD format made use of the fact that not all data-recording surfaces are specified for use in the Red Book CD-DA or Yellow Book CD-ROM standards. CD transports were not able to recover the data hidden in the Cue Sheet unless commanded to by proprietary software. The Cue Sheet specified a broad range of metadata, including number of channels, per track pre-emphasis status, per track copy protection bit setting, per track ISRC Codes, per disc UPC/EAN, etc. (see Compact Disc subcode).

Despite claims to the contrary, only Sonic Solutions' "Sonic System" software was able to generate PreMaster CDs. PMCDs were subsequently obsoleted by the more modern and generalized Disc Description Protocol (DDP) specification. Several factors led to the decline of the PreMaster CD standard. First, the CD-R mechanisms that were able to read and write the hidden cue sheet metadata went out of production in the late 1990s. Second, only Laser Beam Recorders or LBRs manufactured by Sony were able to read PMCDs, which limited the formats adoption by replicators.