Hybrid SACD/DVD (Part 2 of 3)

By Stefan Schreiber

The new proposal

However, there might be a "soft" solution for the ongoing format-war: the introduction of hybrid two-sided discs, with one SACD-layer on one side (at least) and music in the formats DVD-Video and/or DVD-Audio on the second side (maybe the same). This solution works easily, because in the most basic case, a SACD half-disc is glued to a DVD half-disc. The consequence is a normal optical disc (1.2mm), containing "correct" layers for both DVD- and SACD-players. SACD- and DVD-Audio-players will see their respective layers, with the right specifications. Obviously, there isn't any problem concerning "compatibility".

This format (SACD/DVD) has at least two main applications. Firstly, it is probably the only "practical" possibility to include music video into the SACD-standard.

Music video has a broad range of uses and applications (video-clips for pop/rock music, live-concerts, musicals, ballet, operas...). In my opinion music video on videodiscs has a great future ahead, especially combined with high-resolution tracks and surround-sound. Philips and Sony might have thought to extend the SACD-standard for video (using the "Extra Data Area"); however, a new standard SACD-Video wouldn't have any chance beside the (mighty and official) DVD-Video.

Secondly, every record-label would have the possibility to release a record on SACD/DVD-Audio (V), offering both formats in one medium. Of course, this is an absolute future-proof solution for the customer, who knows that at least one of both standards will survive. In this case, a further advantage for the record-label would be that they will not have to consider parallel editions for both DVD-Audio and SACD formats any more, which has happened in some cases and seems to be completely unnecessary now.

Both hybrid SACD/DVD-Video and SACD/DVD-Audio discs can be produced without big problems as "DVD 10" (double-sided DVD) on all existing DVD production lines. A more complete SACD/DVD-Audio/Video disc, containing music and maybe video in three formats, will be manufactured (normally) in a "DVD-14" process. Of course, (at least) one of the used "masters"/matrices for the injection moulding process has to be "cut" as SACD-master by a special Laser Beam Recorder (LBR).

A DVD-14 (I prefer to call it more precisely a "DVD-14", because of the included non-standard SACD-layer) goes through a more complicated process of manufacturing, usually requiring the so-called "Surface Transfer Process" from Time Warner (to manufacture a two-layered DVD half-disc). However, this is a commercially used production process, and not "science fiction". For example, the DVD-Audio editions of AIX Records are usually two-sided discs, three-layered, requiring exactly this kind of DVD-14 manufacturing process.

A single-sided SACD/DVD (read from the same side, one layer SACD, the second layer DVD) can't work. The first problem starts with the fact that both SACD- and DVD-players would expect "their" respective "Lead-in" on Layer 0. DVD- and SACD- Lead-Ins are not compatible and, additionally, a SACD Lead-In would be encrypted. There are different file-systems, and so on.