I am about to build a new htpc solely for use with XBMC and my research has directed me towards an Asus Xonar sound card to pass through DolbyTrue HD and DTS Master HD audio tracks. My question is will XBMC properly playback bluray files with these tracks, and if so do I have to do anything special to enable it? I will be using HDMI from my HTPC to my receiver.
Thanks
bump, subscribed to this one as well. Curious.
Very interested with this as well. I know that the best would be to buy the card and try it out but it's not the cheapest...
as far as i know, DTS-HD and Dolby TrueHD playback only works with special versions of Power DVD or TotalMedia Theater.
Not only the Xonar (be careful: only the HDAV1.3 cards can do this !!!) can bitstream HD audio, there's also the Auzentech Auzen X-Fi Home Theater HD card and (my favorite) the ATI Radeon 5000 series.
the advantage of the ATI cards is, that you don't have to loop your video signal through the sound card - some AV receivers are unable to handle these signals.
The 5000 series indeed looks great. I did not even know about it... Can we hope for added support on xbmc or for some legal reason, it will never happen ?
What I don't know about audio streams could fill a book, but wouldn't it be more dependent on the connected audio receiver than XBMC? If XBMC is instructed to simply stream out the digital audio, then it doesn't do any processing of it, and buying an audio card to handle it won't do anything for you. If your receiver can handle DTS-HD and TrueHD, then it should work regardless of your PC's audio card.
pashdown Wrote:If XBMC is instructed to simply stream out the digital audio, then it doesn't do any processing of it, and buying an audio card to handle it won't do anything for you.
streaming WITHOUT processing is what is called "bitstream"
pashdown Wrote:If your receiver can handle DTS-HD and TrueHD, then it should work regardless of your PC's audio card.
not really. the soundcards or graphic cards send a decoded stream as multichannel LPCM to the receiver (must be HDMI connected) not using the HD audio decoder of the receiver (showing MULTICHANNEL instead of TrueHD or DTS-HD). only the ASUS, Auzentech and the Radeon 5xxx can bitstream HD audio.
Since XBMC does not have the decoders built in (it uses FFdshow) it can not decode all forms of HD audio at this time. Without proper decoding or a PAP HD audio will be downsampled on the way out to the receiver at best. Ripping a bluray with the default HD audio (DTSHD etc) intact will only allow XBMC/ffdshow to play either down sampled PCM or the non-hd track (usually the default dolby or DTS track) out of the audio.
The only way around it, without using something like others suggested (TMT3 or PowerDVD etc which have the HD audio decoders built in plus use the Xonar/other audio cards for PAP) is to convert the HD audio to something like FLAC and then XBMC will play the "HD" audio without needing to decode it specifically. Any HDMI connection can then output the sound without the need for the sound card or the receiver being able to bitstream or decode HD audio themselves.
I'm not sure about the bitstreaming abilities of XBMC (I converted my HD tracks when I archived my blurays) but I think still, without a PAP the audio will be downsampled to 16 bits max instead of 24 although I may be corrected on that.
According to this poster, they have TrueHD working to their receiver. Is that different to what you are trying to accomplish with a soundcard?
... so we need to wait for FFdshow before we can use it. But should it be a 'leave it alone' type of decoding?
Around the post, I think that they are passing it with LPCM, we are looking at passing the raw signal to the reciever and let it do the decoding.