Dolby Digital Live VS PCM with HDMI

Nikana · 01-26-2013, 03:07 AM

Hello all.

I am trying to get an answer to a question that is bothering me.

I have recently went back to PC gaming, and have been using my HTPC in my living room with a 360 controller.

DMC just released and I noticed some things about the audio. My PC is always outputting PCM to each speaker.

During the cutscenes everything is great. All of the vocals go to my center channel, and its nice and crisp. But when the gameplay starts its almost as if the audio levels drop a little but. Almost as if I was using Dolby Pro Logic. Everything just doesn't seem as crisp.

So I was doing a little research and came across sound cards with Dolby Digital Live. From what I am reading it allows sources that are 2 channel, and decodes them into 5.1 on the fly. So each channel gets the right signal etc.

Now my question is, is Dolby Digital Live better than PCM?

My guess is no, because to my knowledge PCM is the output device sending each signal to the precise channels that are available. While Dolby Digital Live is just faking it.

Im thinking that during gameplay, DMC just isn't as robust in the audio department, and the cut scenes are rendered with 5.1 in mind.

Hopefully this makes sense, and if anyone could help that would be great.

Durvelle27 · 01-26-2013, 08:24 AM

No PCM is not better than Dolby Digital/Dolby Digital Live

If you really want 5.1 in games a Dolby Live sound card is the best option. I myself use onboard S/Pidf out to my home theater system and i get PCM w/2.1 Channels. I had a Dolby Live sound card and it does make a nice difference but i put it in my HTPC because it need S/Pdif and Coaxial

Nikana · 01-26-2013, 01:23 PM

Can you explain why it is better?

I have been doing more research and it seems like Live is worse because it is horribly compressed. While PCM is not compressed.

fuzzymath10 · 01-27-2013, 05:47 PM

If you're stuck with optical or coaxial SPDIF, then the only way to get 5.1 is through compressed audio, in which case DD Live would work well. PCM will be only 2 channels.

With HDMI, you no longer have that issue because new video cards can send out 7.1 uncompressed channels to your receiver.