Confused about Audio Path/Setup

dereksbelanger · Post by **dereksbelanger** » Tue Nov 03, 2009 7:10 am

Hey gang! My interest in SPCR began when I decided to build a quiet HTPC. Iâ€™ve done that â€“ itâ€™s not perfect â€“ but good enough for now.

There is, however, something about HTPC computers that confuses me completely â€“ the audio path. Consider:

An HTPC will have one or more sound card.
There are probably SPDIF and headphone ports on the sound card
The GPU/IGP probably has HDMI with audio
You can put an amp in your PC (http://www.msi.com/index.php?func=prodd ... d_no=1654#)
OR you can connect your PC to a receiver with any one of the audio connectors on your soundcard/MB/GPU/IGP
Then there is software: video drivers, decoders, players and OS â€“ and each of these has influence of how the hardware works.

Anyway - I just canâ€™t make sense of it all. It seems like a big fat mess to me. Can anyone make sense of it for us newcomers?

Thanks!

Michael Sandstrom · Post by **Michael Sandstrom** » Tue Nov 03, 2009 11:42 am

How can anyone address your concerns without knowing which OS you are running and what you are trying to accomplish?

dereksbelanger · Post by **dereksbelanger** » Tue Nov 03, 2009 1:40 pm

Michael Sandstrom wrote:How can anyone address your concerns without knowing which OS you are running and what you are trying to accomplish?

Easy! You could start by saying something like...

"I know! Its crazy that there are so many audio ports on a PC - and its especially weird that there is an audio port on video cards! Anyway each port suits a different application and it breaks down like this:

* This is why there is an audio port on video cards and this is why/when you should use it.

* This is why there is SPDIF on your sound card and why/when you should use it

* This is why there are 5.1-7.1 headphone jacks on a soundcard and this is why when you should use them.

* Yeah - built in PC amp is really cool and this is why/when you should use it"

Once we have that (the hardware options) sorted out we can talk about software.

audiojar · Post by **audiojar** » Tue Nov 03, 2009 2:03 pm

Just think of the PC as another media source in a typical home theater/stereo setup. You have a CD player, DVD/Blue Ray player, probably a cable or satellite box, etc. You need some sort of switcher to manage all of these sources, usually that's an AV receiver (or a TV if you are using it for sound and it has all the inputs you need). In this broad sense the PC is just another media source.

As far as how to best connect it to your system, well that depends on what you are using. The ideal situation is probably an AV receiver with HDMI. HDMI carries audio and video in one cable, this makes it very nice on cable clutter and simplifies everything (assuming everything is using it). For a PC you are taking the digital output of the sound card and the digital output of the video card and combining them in to a single HDMI output (which then gets treated like any other source). If you are using a DVI to HDMI adapter it will have a SPDIF input for digital audio from your sound card. If you video card has HDMI built in then it will pipe the audio through.

You would do something similar for a less modern system not based on HDMI. It would just involve multiple cables for each source device. You can also mix and match, like component (or if non-HD, composite or s-video) video and SPDIF audio.

Mr Evil · Post by **Mr Evil** » Tue Nov 03, 2009 6:30 pm

For HT, I reckon the best solution is a graphics card/IGP that supports 8-channel LPCM out of the HDMI connector, and a receiver that has a suitable input for it. I say this is the best solution because everything else is either analogue, lossy or only stereo. The only problem is the stupid DRM, which causes confusion.