Audio output via both S/PDIF and HDMI?

I've got a similar question. My receiver doesn't have HDMI, so I was planning on running an HDMI from my HTPC (the onboard output from my gigagbyte h55m-ud2h) to my TV (Panasonic TC-P50V10), and then optical output from the TV to my receiver. That'll work for movies, right?

But if if I want to play music on my HTPC, I assume I need to run an optical direct to the receiver, right?

So if I have both the HDMI and optical outputs connected from my HTPC, is that going to confuse it?

Or, do I even need the optical output from my TV to the receiver? When playing movies, could I just send the video to the TV via HDMI and the audio to the receiver via the HTPC's optical output? That would be the simplest thing if it can be done.

Unfortunately, I cannot answer the OP question because I will eventually have the same setup and will need this question answered. But for mirak, I do know (unless it's different for an HTPC than a DVD/Blu-ray player) that if you hookup an HDMI from your HTPC to your TV and then send the optical audio from your TV to your receiver, you will lose your digital surround sound. The TV only sends a stereo signal from its optical audio output, unless it is from an OTA TV signal.

Hopefully someone else can answer the main question.

You just have HDMI to TV and optical to receiver from PC - then you tell the PC to use S/PDIF for everything and as your default audio - you will never use audio on the TV. This would be the best way to set it up.

Not in Vista or 7 I don't think, no. Unless the application supports outputting to both at once, then I guess it might be possible.


Why not just use the hifi system for both types of audio? Or is it in a different room or something?

The easiest way to do that otherwise is just set Windows to use HDMI audio as the default and then use a music program where you can set the audio output device independently of the Windows default playback device (most 3rd party programs can do this--WinAmp, MediaMonkey, etc. should all be able to). So then you set your music player to output to the S/PDIF device (and not the Windows default) and off you go.

This usually isn't possible, as most TVs, if not all, do not pass through the DD/DTS signal over their SPDIF Out unless it is from an OTA source so all your receiver would be getting is 2 channel PCM audio. As stated, the best way to connect is to use SPDIF from your PC to your receiver.

It's an OS limitation and not hardware. It may be due to complex issues for the OS to know what to do. Say you have a DD source. The OS knows to pass through the DD signal on a HDMI and SPDIF signal, but if also transmitting to analog speakers, then the internal sound card has to decode the DD source and use its DAC. Maybe due to issues like this the devs decided to only allow 1 device selection at a time.

AFAIK, KMPlayer allows output to second device.

Would something like this help?
http://www.ambery.com/2hddodtsdihd.html

It has HDMI in and HDMI, analog and optical out.

Yes it might work with XP and it would probably even work with Vista/7 if it were an AC97 sound device (not sure about this because I've never used an AC97 device in Vista). Because AC97 I don't even think it was capable of outputting different streams. The way the path was routed for AC97 was fixed 48kHz, and then the analog out was just a D/A conversion of the digital out. In 2ch PCM I mean. In bitstream (DD/DTS), the analog out would be off/silent.

But in Vista and with HD Audio (aka Azalia) the output devices are different. Like the digital output acts as if it were a separate soundcard altogether, you don't get simultaneous output on both digital and analog outs, not from the same stream. It might be possible for an application to output to two devices at the same time; but, I don't think I've seen an app that can do that; and, you're using VMC/7MC so that is out of the question anyway.


Ah I see. Makes sense.


Yeah there you have a problem because you aren't going to be able to do it automatically. You're going to have to select your default output device everytime you start VMC/7MC or WMP, because MS never designed a feature to use different outputs on different media playback.

The only other way around this is forget using digital output altogether. Use analog stereo output to the TV, and then (assuming your TV will be on when you are playing music) use the analog out from the TV to the receiver. If your TV will not be on when playing music, then you can split the output to go to both inputs by using simple RCA splitters or a headphone jack splitter at the PC's output and then two Y-cables into that.

The only thing I dislike about analog out from PC sound cards (particularly built-in sound cards) is the relatively low output level. But you gotta make some sacrifices/comprimises to get what you want. Either you are going to have to switch output devices, use other programs, or go analog...

Using the analog also screws you over in that it will use the crappy on-board PC DAC instead of the good quality DAC I'm assuming you have in your receiver, since I don't know what your receiver is.