The Guide to HD Audio with a HTPC - How to Get TrueHD and DTS HD Master

TLS Guy

TLS Guy

Seriously, I have no life.
Cable mess! Do something about it and the temp will drop a little.
That was while it was still under construction. Everything was very tidy by the time the panels went on.
 
R

roots4x

Audiophyte
I don't know if this has been confirmed or not, but no current generation video cards (ATI 4xxx, Nvidia GTX 2xx) support PAP audio bitstreaming. The only solutions are the xonar, xonar slim, and the auzentech HD 1.3 whatever it's called.

Nvidia is releasing a new card with a new chipset, the GT220 and G210 HDMI cards. Those are HDMI 1.3a spec but not sure if they support bitstreaming yet as they are OEM only cards and no one really has them.
 
GlocksRock

GlocksRock

Audioholic Spartan
any idea when those new cards will be available?
 
F

fredk

Audioholic General
Q3 2009.

It would be nice if this chipset is truely HDMI 1.3 compliant. I have just about given up hope and am looking at stand alone bd players.
 
R

redass

Junior Audioholic
wonder if anybody can answer this or if there is an answer...

on Arcsoft TMT3, how does one confirm that they are getting HD audio out of a bluray or HD DVD? The settings are there, but is there a way to display or confirm HD audio output? I've got it decoding and sending audio through the analog outputs on my x-fi but obviously there is no way to know what is really coming out unless the software tells me.
 
J

jakmal

Audiophyte
The OPs initial informative post indicated why it is not possible to bitstream DTS-HD / TrueHD (because of AACS / PAP).

The question I am about to ask has been put forth in many other forums, but no suitable answer has been found.

Q1: How can NMTs like Popcorn Hour bitstream DTS-HD / TrueHD while ATI 4600 and 4800 can't?

Q2: Why can't MKVs with DTS-HD and TrueHD tracks inside them (obviously AACS is removed, as is any content protection) have their audio tracks bitstreamed out through the high end ATI HTPC cards?

Q3: ATI's website says that the maximum supported bitrate for DTS-HD and TrueHD even for these 4600 and 4800 cards is only 6.144 Mbps. Why are software applications unable to treat the DTS-HD and TrueHD tracks as just raw data and send them out through these HDMI ports?

I know that the Blu-Ray spec states that the maximum audio quality for these lossless HD audio codecs is at 24 bits , 192 KHz , 7.1 channels. The bitrate which needs to be supported at the interface then works out to be 36.864 Mbps. Since only 6.144 Mbps is supported, it is possible that this is the reason for the inability to bitstream. However, users on the AVS Forums have found that it is possible for LPCM output from HDMI to be 7.1 channel, 192 KHz , 32 bit quallity:

http://www.avsforum.com/avs-vb/showthread.php?t=1029603

The bandwidth at the output then works out to be 49.152 Mbps! This is much higher than the maximum allowed DTS-HD and TrueHD bandwidths. It remains a puzzle why bitstreaming hasn't been demonstrated (on Linux / open source apps) yet on these ATI cards. Which application would be the best to implement this? I am thinking Reclock or AC3Filter. What is the opinion of fellow forum members!

Thanks for your attention.
 
Last edited:
GlocksRock

GlocksRock

Audioholic Spartan
Q3 2009.

It would be nice if this chipset is truely HDMI 1.3 compliant. I have just about given up hope and am looking at stand alone bd players.
Q3 2009... They better hurry up and release them then, since it's almost Q4. I'm anxious to see what they put out, and how much it costs.
 
F

fredk

Audioholic General
wonder if anybody can answer this or if there is an answer...

on Arcsoft TMT3, how does one confirm that they are getting HD audio out of a bluray or HD DVD? The settings are there, but is there a way to display or confirm HD audio output? I've got it decoding and sending audio through the analog outputs on my x-fi but obviously there is no way to know what is really coming out unless the software tells me.
If you are sending it to an analog out, it is no longer HD. Anything sent to an analog output will be down sampled. If you dig deep into protected audio/video path info, you will find that it is possible for content providers to define a policy for their content such that they can decide to down sample to analog out, or even turn off analog out.

The only way to get HD audio to your speakers is through HDMI to what is considered a secure endpoint (your receiver).
 
F

fredk

Audioholic General
Q3 2009... They better hurry up and release them then, since it's almost Q4. I'm anxious to see what they put out, and how much it costs.
From the specs I saw quoted in releases, and others comments, these will not be high end cards in terms of memory and gamer spec. stuff, so I would hope that the are in the $50-$100 range, but who knows.
 
M

mustang_steve

Senior Audioholic
Definate Kudos for this thread. It looks like I now know the card I need for my HTPC, the Asus Xonar HDAV. Having the ability to merge the audio stream with the video stream is a huge plus...and the Dolby Ditigal Live support is something that's very relevant since I game.

I've lacked DDL support since 2004, when I needed a faster PC...RIP to my old NForce2 motherboard.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
I've had first-hand experience with the Asus Xonar HDAV1.3 & TMT3.

You set the Asus Xonar control panel/setting to HDMI audio + 5.1 or 7.1 configuration. The default is retarded because it is set to analog audio. You have to manually change it to HDMI audio.

Then on your OS, you have to make sure it is set to Asus Xonar Speakers, which should be the default after you install the Xonar software.

Then on TMT3, you have to set to HDMI PASS-THROUGH. This will bitstream PCM, TrueHD, and DTS-HD MA to your receiver.

On your receiver, the LCD will read Dolby TrueHD, DTS-HD MASTR, or MULTI-CHANNEL DIRECT (PCM). This is the ONLY way you can be 100% sure that you are TRULY getting the HD Audio. If you use ANALOG, you MIGHT be getting the HD Audio. But you might NOT.:D
 
lsiberian

lsiberian

Audioholic Overlord
It's what we do. :D

To the common man, if it ain't broke don't fix it. To the engineer, if it ain't broke it doesn't have enough features yet. ;):cool:
speak for yourself. I'm not putting effort into something that works.

Oh wait my home theater! NM.
 
s162216

s162216

Full Audioholic
Definate Kudos for this thread. It looks like I now know the card I need for my HTPC, the Asus Xonar HDAV. Having the ability to merge the audio stream with the video stream is a huge plus...and the Dolby Ditigal Live support is something that's very relevant since I game.

I've lacked DDL support since 2004, when I needed a faster PC...RIP to my old NForce2 motherboard.
Thanks - the DDL is actually one of the best and useful audio technologies ever done IMO. Pity its not included in many cards and an even greater pity that Nvidia discontinued Soundstorm and as so the DDL for many people. Its such a shame the new 7.1 soundstorm they mentioned in passing a few years ago as what was suspected to be an internal card never materialised.

I still use my NForce 2 Asus A7N8X-E deluxe as my main PC, its perfect as a HTPC and for pre late 2007 games.

About the analogue out - according to HDCP etc you should get full quality HD audio without any restrictions if its been decoded.

The person who said once audio is analogue it is no longer HD is wrong - if theres been no downsamplng then its just the PCM/bitstream decoded into 8 separate electrical signals which can then be amplified by the reciever.
 
Y

yrk1959

Audiophyte
You dont need a Xonar or like for HD Audio

Hello Everyone,

As I have understood and experienced. it is possible to get HD Audio without these fancy cards like Xonar.
...as long as your happy with PCM at the same rate as the original being pushed out to your reciever and don't care about the fancy TrueHD/HD MA lights.

If you use TMT3, without Xonar, it will decode and downsample TrueHD/HD MA to PCM 16/48 over HDMI. So if you have DTS HD MA in 24/48 (e.g. Day After Tomorrow), it goes out as PCM 16/48. Some loss.

However, if you use older versions of TMT (2.x.125 or lesser), they did not downsample. They decode and output at the same rate e.g. 24/48 above.

I have tried such a version and can confirm that output was 24/48 (using ReClock).

regards
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Hello Everyone,

As I have understood and experienced. it is possible to get HD Audio without these fancy cards like Xonar.
...as long as your happy with PCM at the same rate as the original being pushed out to your reciever and don't care about the fancy TrueHD/HD MA lights.

If you use TMT3, without Xonar, it will decode and downsample TrueHD/HD MA to PCM 16/48 over HDMI. So if you have DTS HD MA in 24/48 (e.g. Day After Tomorrow), it goes out as PCM 16/48. Some loss.

However, if you use older versions of TMT (2.x.125 or lesser), they did not downsample. They decode and output at the same rate e.g. 24/48 above.

I have tried such a version and can confirm that output was 24/48 (using ReClock).

regards
Last time I did it, I could only get PCM 2.0 via HDMI on TMT3 (without Xonar). I was not able to get 5.1 PCM via HDMI.

So you are saying that TMT3 can decode 5.1 TrueHD & 5.1 DTS-HD to 5.1 PCM via HDMI?
 
Y

yrk1959

Audiophyte
Last time I did it, I could only get PCM 2.0 via HDMI on TMT3 (without Xonar). I was not able to get 5.1 PCM via HDMI.

So you are saying that TMT3 can decode 5.1 TrueHD & 5.1 DTS-HD to 5.1 PCM via HDMI?
Yes, it did decode.

I had to setup Speakers as 7.1 in Vista/Control Panel/Sounds and output as 5.1 (and not HDMI, I think) in TMT3.

There was a difference in loudness (or it sounded different, can't say exactly) when I compared this output with a standalone Blu-ray player (set to bitstream to amp). Thats when I researched a bit and came to know that TMT3 was doing 16/48 vs 24/48 on the standalone player.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Yes, it did decode.

I had to setup Speakers as 7.1 in Vista/Control Panel/Sounds and output as 5.1 (and not HDMI, I think) in TMT3.

There was a difference in loudness (or it sounded different, can't say exactly) when I compared this output with a standalone Blu-ray player (set to bitstream to amp). Thats when I researched a bit and came to know that TMT3 was doing 16/48 vs 24/48 on the standalone player.
Well, that should give me something new to do tonight.

Project TMT3 5.1 PCM HDMI.:D

Yeah, for some reasons, I was only able to get 2.0 PCM HDMI before. It's probably something really simple. But I will make sure that the TMT3 is set to 5.1 Speakers, instead of HDMI.

Have you tried playing a blu-ray with LPCM as the soundtrack (i.e. The Rock)?

I did that once, and got no sound at all.:eek:
 
GlocksRock

GlocksRock

Audioholic Spartan
I will have to try this as well... hopefully it will work, it would be even better if I could get it to work in PowerDVD.
 
Y

yrk1959

Audiophyte
Have you tried playing a blu-ray with LPCM as the soundtrack (i.e. The Rock)?

I did that once, and got no sound at all.:eek:
Dont have The Rock, but I just tried Spider-man 3 with TMT2.
Its has PCM 16/48 and TrueHD 24/48. Both came out fine.

Though, why they put in PCM 16 with TrueHD 24-bit is beyond me.
 
newsletter

  • RBHsound.com
  • BlueJeansCable.com
  • SVS Sound Subwoofers
  • Experience the Martin Logan Montis
Top