Dolby Digital Question

[DP1962]

I have a Dish 500 with a DVR 625 and can't seem to get Dolby Digital audio out of it. I hooked my surround sound to the digital audio out and everything seems to be PCM. I went into the Dolby Digital setup menu and there are three choices: Dolby Digital/PCM (which it was set to) Dolby Digital, and PCM, so I tried setting it to the Dolby Digital only and I get no audio, I run through all the available decoder choices on my surround sound plus select the auto detect feature and I get nothing, setting the Dish receiver back to Dolby Digital/PCM and I get sound via PCM. (what does PCM stand for?)

The question(s): how many channels/programs are supposed to be available in Dolby Digital with the 625? Are there any other setup issues to get Dolby Digital from the 625? My surround works fine on Dolby Digital from other sources so I'm pretty sure there's no problem with the surround receiver.

Thoughts?

 

[ats7627]

PCM stands for Pulse Code Modulation. Dish uses Linear PCM. Linear PCM is an uncompressed audio format. It can have up to 8 channels of audio at 48khz or 96khz sampling frequency.

Some PPV Movies are in Dolby Digital. Select movies on HBO, Starz, Cinemax and Showtime are in Dolby Digital. Look for the Dolby Digital symbol (DD) in the program guide.

Most of the HD channels are in Dolby Digital. Since you have a 625, they do not apply.

 

[DP1962]

Thank you for your response.

Next question, this is getting away from a Dish question but I'll ask anyway, should there be a dramatic difference for a surround sound system between Dolby Digital and PCM? My new surround sound system sounds terrible on PCM, either from the Dish receiver or the analog over the air through the TV, yet sounds wonderful on Dolby Digital from HD over the air, PCM is terrible no matter what surround settings or combination thereof I set the system to.

 

[Julien]

PCM stands for Pulse Code Modulation. Dish uses Linear PCM. Linear PCM is an uncompressed audio format. It can have up to 8 channels of audio at 48khz or 96khz sampling frequency....

Most of the HD channels are in Dolby Digital. Since you have a 625, they do not apply.

Actually all HDTV channels are Dolby Digital as per the ATSC standard. It may be 2.0, 2.1, 3.0,..., or 5.1 but it is all DD. Also the LPCM output is not LPCM off the satellite (too much bandwidth). It is probably lossy MPEG2 compressed audio (hence the "bad" sound) converted to LPCM for SPDIF output.

 

[DP1962]

Another question, if only a few PPV movies and select movies on HBO ect are DD why does the setup menu of the 625 have a setting for DD only? Unless this setting is supposed to provide at a minimum DD 2 channel audio regardless?

 

[ats7627]

If you select Dolby Digital only in the setting, you will not get any sound unless the program has Dolby Digital.