Are current SSP's 640kbps-DD compatable?

[BTT917]

With the new disc / Dolby audio formats around the corner, which can be delivered digitally as 640kbps DD, does anyone know if current receivers / SSP's are spec'd to accept that high a bitrate?

 

[jcPanny]

Not yet.

I am not aware of any receivers that accept a Dolby HD digital feed. First, the receiver would require a firwire or HDMI connection to receive that digital signal. HDMI v1.3 will support Dolby HD would be required and it hasn't even been finalized yet.
About a year from now when HD and BluRay players and media are available, high end receivers will start to support these features. In the mean time, the player will decode the signal and output over the analog outputs to the receiver.

 

[j_garcia]

DTS comes in a full bitrate version of 1509k, and standard DTS is 748k, and all DTS capable can handle that, so the answer would seem to be yes. However, current receivers won't have the right decoders for those formats.

 

[BTT917]

Thanks for the replies.

I know that no current SSP can handle raw Dolby TrueHD or DTS-HD. All HD-DVD / BD players can output decoded TrueHD or DD+ via SPDIF as 640kb/s standard Dolby Digital as a "backwards compatability" feature, so you don't have to utilize the analog outputs of the player to listen to the TrueHD / DD+ track. That 640kb/s signal compatability is what I don't know, as I've never seen that spec published, and in "Secrets SSP Benchmark" they list it as a test but have never recorded a score for that feature.

Here is a quote from Dolby's TrueHD website:

http://www.dolby.com/consumer/technology/trueHD/AVRs/trueHD_avrs_2.html

"S/PDIF Connection
If your A/V receiver or processor has neither multichannel analog or digital inputs, but is equipped with 5.1-channel Dolby® Digital decoding and playback, you will still be able to enjoy 5.1-channel performance from next-generation optical players. Included within 7.1-channel multichannel Dolby Digital Plus and Dolby TrueHD streams is a core 5.1 mix prepared by the content maker that is used when the player is set for 5.1-channel mode. After playback audio signals have been mixed in the player, the PCM signal can be encoded to a Dolby Digital signal and output from the player via S/PDIF (optical or coaxial) to your connected Dolby Digital A/V receiver or processor."

"In many instances, the audio quality you will experience from this connection may be better than what you would experience during playback of standard-definition DVD-Video discs, especially if the native signal on the disc is Dolby TrueHD or high-bit-rate Dolby Digital Plus. This is a direct result of a higher-quality source signal feeding a Dolby Digital encoder running at 640 kbps—higher than the maximum bit rate on DVD-Video."