DDP (Disc Description Protocol, written and owned by Doug Carson & Associates) masters are a truer representation of your product than an audio CDR master, sometimes referred to as ‘PMCD’. Actually, the term PMCD was coined, and actually owned, by Sonic Solutions who was a pioneer in making masters on CDR with their mastering software. And, theoretically, a PMCD could only be made using a Sonic Solutions digital audio workstation.

In actuality, a PMCD was just a true Red Book CDR. The formatting of a Red Book CD involves using a specific error correction scheme in which errors are corrected, and sometimes interpolated, at the CD player during playback. CD players use parity and interleaving techniques to minimize the effects of an error on the disk. But, it’s like playing back through a ‘screen door’. In theory, the combination of parity and interleaving in a CD player can detect and correct a burst error of up to 4000 bad bits — or a physical defect 2.47 mm long. Interpolation can conceal errors up to 13,700 or physical defects up to 8.5 mm long. If there are too many errors, the CD player will just interpolate samples to get a reasonable value. If it can’t correct that error, it will simply mute. If you use a Red Book CDR as a data source for the Glass Masterring process at the plant, the disc must be ‘played’ (rarely at real time, but most of the time at 2x) and the errors on the disc, including any interpolated errors, will be passed on to the Glass Master and subsequently to every replicated copy.

In reality, the Red Book CDR (or PMCD) is a copy of the original audio that must be played back through this ‘screen door’ error correction scheme on it’s way to the Glass Master. When you hear the replicated CD, you’re actually hearing the audio after it has passed through yet another ‘screen door’ in your CD player. Whereas, a DDP Master IS the actual audio transferred to the Glass Master as data , and when you hear the replicated CD in your CD player, you’re hearing the audio that has only passed through one ‘screen door’– the one on your CD player. This is why we prefer delivering plant masters in a DDP format. We provide these on a Yellow Book CDROM, DVD-ROM, or electronic transfer.