4 replies to this topic

[GAT474]

I gifted myself a couple of blurays for Christmas and noted one had the soundtrack options of dolby digital and dolby digital PCM. When I selected the PCM version my receiver showed it was receiving a signal via the multi channel input and the dolby digital version was as per normal. I'm using a Pana bluray player connected to a Denon 2310 via HDMI.

Does anyone know the difference between the two?

[davewantsmoore]

DD = (lossy) encoded AC3 audio (decoded to PCM by your device)
DD PCM = not encoded in AC3 ... could be better ... depending on number of channels, bit rate, etc. compared to the above.

[joz]

From memory it will wil multiple channel PCM which will be at a much higher bitrate than plain vanilla DD.

It should sound better.

[GAT474]

Thanks for the info. I take it that the PCM will still not be in the same league as DD HD or the DTS HD?

[davewantsmoore]

From memory it will wil multiple channel PCM which will be at a much higher bitrate than plain vanilla DD.

Perhaps, but not necessarily. DD could be stereo or multi ... and DD PCM could be either 2 or more channels.

In the past, I've found it common for there to be a DD (AC3 surround) track, plus a PCM (lossless stereo) track .... AFAIK due that being what would fit on the media.

Thanks for the info. I take it that the PCM will still not be in the same league as DD HD or the DTS HD?

Again, probably but not necessarily. Both are lossless, however the bit/sample rates of either could AFAIK be anything .... The HD audio formats do generally offer the higher bit/sample rates when they are available of course.