Digital Media Thoughts has word on a new announcement from Dolby Laba at CES:
“Dolby Digital Plus builds on the original Dolby Digital specifications, allowing for higher bit rates and more channels. Dolby Digital Plus has a maximum bit rate of 6mbps, and support for 13.1 channels. In comparison, Dolby Digital caps out at 640kbps and 5.1 channels. So Dolby Digital Plus essentially provides 10 times the bandwidth of the original Dolby Digital. The new format also allows for extremely low bit rate multichannel sound for streaming on the Web or over the air. The benefits of the Dolby Digital Plus codec include transient prenoise processing, enhanced channel coupling, adaptive hybrid transform processing, and channel and program extensions.”
I live in a ritzy part of town, and I know a few folks who have big houses. But I can’t imagine any home theater that needs thirteen channels of sound. I’m not even sure my local multiplex has any theaters that need that many channels.
I can only imagine how deafened I would be if I were walking around the show floor at CES.
Ed Bott 
Hi,
Just to give you a bit of information regarding Dolby Digital Plus and when it will be arriving.
Dolby Digital Plus is an enhancement to Dolby Digital which effectively increases the number of sound channels that can be carried in the same bandwidth. The number you may have heard is 13.1 channels – which is true, Dolby Digtal Plus can theoretically carry 13.1 channels of sound in the same ‘space’ as 5.1 Dolby Digital.
However don’t expect Dolby Digital Plus equipped home theatres to come with 14 speakers any time soon. Dolby Digital Plus was designed to allow HD broadcasters and HD-DVD/Blu-Ray producers to provide the same 5.1 stereo sound, but leave more bandwidth available for the picture (which requires substantially more bandwidth over SD).
Another option is that broadcasters and Disc producers could produce a 5.1 multichannel soundtrack, a 2.0 Stereo soundtrack (which could, of course, be matrix-encoded for ProLogic 2 systems), a 2.0 descriptive soundtrack for hearing-impaired viewers, and a 2.0 “Director’s Commentary” soundtrack all in the same bandwidth normally occupied by 5.1 Dolby Digital.
Dolby Digital Plus (we don’t refer to it as DD+ BTW) is also part of the Blu-Ray standard as an option (same as DTS) as well as HD-DVD. It has also been accepted as part of the ATSC (US HD standard) and DVB-T,-S and -C formats in Europe as options. It was specifically designed for use with MPEG4 (H.264) transmission codec.
The Dolby Digital Plus compression codec is extremely effective, as you noted above. But it is also extremely flexible, allowing low bitrate channels where required or, when used in high bit-rate ‘mode’ can provide up to 24-bit Audio Resolution. The stream can provide up to 6Mbps speeds, but is limited by the various media to a maximum of 3Mbps. It can support bitrates as low as 30kbps where necessary. This flexibility means that we can supply almost bit-for-bit quality for discs down to low quality for IPTV without all from the same source (no need for further mastering).
Don’t forget that for HD-DVD and Blu-Ray we have Dolby TrueHD which is a lossless audio codec for HD disc formats – every bit that was in the original recording will be reproduced in the home.
Sorry for rambling – I hope you find this information useful. If you have any other questions please drop me a line and I’ll help you out where I can.
regards,
S.