Stereo and Multi-channel on one disc.
Direct Stream Transfer (DST) loss-less coding makes it possible to store 70-80 minutes of both stereo and multi-channel DSD content on a disc. Separate data areas are provided for stereo and multi-channel content, giving artists the flexibility to provide two discrete mixes of the same content on a disc.
Moreover, an “extra data” area has been reserved for expansions of the format that will make it possible to include information such as lyrics, credits, and still images in the future.
In general, there are two types of bit rate reduction technologies. One is DST: loss-less coding, and another is “Lossy”. Data reduction actually chooses parts of the signal that can be ignored, for example, based on psychoacoustic models. Examples include MPEG-1 and MPEG-2 for video, ATRAC, Dolby® Digital (AC-3® ) and DTS® for audio.
All Super Audio CDs containing multi-channel DSD content will carry the “Multi-ch” logo to indicate that they are capable of providing multi-channel sound when played on a multi-channel compliant Super Audio CD player.
Super Audio CD Multi-channel audio software applications.
Faithful rendition of concert hall ambience is just one of the many possibilities of Super Audio CD multi-channel sound. The discrete surround channels, which are totally separate from the main front channels, can theoretically be used to record any content the artist or producer desires, whether it be sound effects, choruses located in the rear, or other innovative recording techniques. Moreover, archived 3-channel and 4-channel recordings can be faithfully re-released in the Super Audio CD format, while the future may bring a variety of new multi-channel recording methods yet to be invented.
Speaker placement in a Super Audio CD Multi-channel playback system.
A typical multi-channel Super Audio CD playback system includes a multi-channel capable player, a multi-channel power amplifier, and a corresponding number of speakers. As shown in the chart, five speakers typically surround the listener in circular fashion in accordance with ITU recommendations and the sixth channel is used for low frequency enhancement (sub-woofer).
Speaker placement in accordance with the ITU-R BS.775 recommendation: the sixth channel can be optionally used for low-frequency enhancement.
Super Audio CD content protection is built with five lines of defense. Each line provides different obstacles against piracy. The independency of these lines of defense means that, even if one of the lines is broken, the others still protect the content against piracy.
- First line of defense: Existing PC disc drives cannot read data from Super Audio CD disc.
- Second line of defense: If Super Audio CD data has been copied, it cannot be used.
- Third line of defense: Hacking the scrambling of a title is expensive and must be done for each new title again.
- Fourth line of defense: Details of the scrambling system are never exposed.
- Fifth line of defense: Sophisticated protection against commercial piracy and counterfeiting.
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