Soundcard for blu ray HTPC

LxMxFxD4

Senior member
Oct 6, 2007
359
0
0
I Have a newly built HTPC. It has bluray that I watch using PowerDVD 8 ultra. PowerDVD (as far as I know) software decodes DolbyTRUE HD and DTS HD sound streams and sends them decoded to optical link of sound card.

At the moment my HTPC uses the onboard audio 5.1 setup via analog.. but I am upgrading to some nice speakers this week that will use an optical s/pdif.

So my question is this: I have a soundcard that was $20 a few years ago but has a really tasty S/N ratio and uses this chipset:

http://www.via.com.tw/en/produ...ontrollers/envy24ht-s/

Exact sound card:
http://www.newegg.com/Product/...x?Item=N82E16829120103 (now deactivated)

I got this because the audio quality is really amazing, but I want to make sure it wont mess / is good enough for blu-ray via optical out to speakers. Meaning, there wont be any compression at any point. If not, please let me know.

Also, if not is there anything out there that WILL play well with 5.1 speakers that you can recommend?

Thanks!
 

s44

Diamond Member
Oct 13, 2006
9,427
16
81
1. Optical can only carry regular DD and DTS. All superior digital audio has to go over HDMI.

2. Because of this, separate sound cards are useless for digital. It all depends what audio hardware is on the video card.

3. Only one video card does a proper implementation of the Protected Audio Path (PAP) -- but it's made by S3, so there's basically no support for it.

4. Because of the lack of PAP, even the video cards that DO implement surround PCM over HDMI (none implement bitstreaming) have to downsample the audio to 16-bit/48kbps (from a max of 24-bit/96kbps on some Blu-Rays) per channel. This is about CD quality, so you may not notice, but then again... You may.

5. Even if one of the big video card makers made a card with HDMI audio and a PAP, the downsampling is in all the software packages, so it might take yet more time for the software players to use the functionality that the PAP allows.

6. Besides S3, only ATI makes discrete cards with full multichannel PCM audio over HDMI. Nvidia only has 5.1 DD/DTS over HDMI, which defeats the purpose. *However*, motherboards are the reverse -- there is no AMD/ATI chipset/mobo that does PCM audio over HDMI, while the Nvidia 8200/8300/9300/9400 has this capability built in. Hybrid SLI will allow you to use a better vidcard with one of these integrated Nvidia HDMI chipsets, if you have it.

7. You can sort of get around the downsampling on these discrete ATI/integrated Nvidia HDMI solutions by ripping the Blu-Ray audio tracks and playing them back as lossless FLAC. However, I shouldn't have to mention what a gigantic pain in the ass this is.

8. There is another workaround being developed -- a card that's supposed to take HDMI video in and add full multichannel PCM or even lossless bitstreamed audio to a separate HDMI out. This is going to be expensive, kludgy, and may never get proper software support. But if you want to waste money... It is, IIRC, the Asus Xonar HDAV.

9. Analog may work... Except computers tend to have lots of other currents running around that mess with the sound. But if you have an analog card that works, don't mess with it!

10. This is a bad, bad time to be building a HTPC. If you can (and I realize you, the OP, probably can't), wait six months for the tech to mature some.

11. The only sort of HTPC I'd personally consider now is one built around this unique MSI mobo -- with a built-in amp.
 

LxMxFxD4

Senior member
Oct 6, 2007
359
0
0
Originally posted by: s44
1. Optical can only carry regular DD and DTS. All superior digital audio has to go over HDMI.

2. Because of this, separate sound cards are useless for digital. It all depends what audio hardware is on the video card.

3. Only one video card does a proper implementation of the Protected Audio Path (PAP) -- but it's made by S3, so there's basically no support for it.

4. Because of the lack of PAP, even the video cards that DO implement surround PCM over HDMI (none implement bitstreaming) have to downsample the audio to 16-bit/48kbps (from a max of 24-bit/96kbps on some Blu-Rays) per channel. This is about CD quality, so you may not notice, but then again... You may.

5. Even if one of the big video card makers made a card with HDMI audio and a PAP, the downsampling is in all the software packages, so it might take yet more time for the software players to use the functionality that the PAP allows.

6. Besides S3, only ATI makes discrete cards with full multichannel PCM audio over HDMI. Nvidia only has 5.1 DD/DTS over HDMI, which defeats the purpose. *However*, motherboards are the reverse -- there is no AMD/ATI chipset/mobo that does PCM audio over HDMI, while the Nvidia 8200/8300/9300/9400 has this capability built in. Hybrid SLI will allow you to use a better vidcard with one of these integrated Nvidia HDMI chipsets, if you have it.

7. You can sort of get around the downsampling on these discrete ATI/integrated Nvidia HDMI solutions by ripping the Blu-Ray audio tracks and playing them back as lossless FLAC. However, I shouldn't have to mention what a gigantic pain in the ass this is.

8. There is another workaround being developed -- a card that's supposed to take HDMI video in and add full multichannel PCM or even lossless bitstreamed audio to a separate HDMI out. This is going to be expensive, kludgy, and may never get proper software support. But if you want to waste money... It is, IIRC, the Asus Xonar HDAV.

9. Analog may work... Except computers tend to have lots of other currents running around that mess with the sound. But if you have an analog card that works, don't mess with it!

10. This is a bad, bad time to be building a HTPC. If you can (and I realize you, the OP, probably can't), wait six months for the tech to mature some.

11. The only sort of HTPC I'd personally consider now is one built around this unique MSI mobo -- with a built-in amp.

Awesome, awesome and informative post sir. Thanks a million for this information. Amazing!

That said, at this point im all very very confused. I built the HTPC, and im not too worried... im out $277 but I have blu-ray video. Computer equipment is dirt cheap these days.

As I mentioned in my post, im buying new speakers - I will probably get the Logitech z-5500 speakers - it has a built in DD and DTS decoders, and I realize I would probably want to use the optical S/PDIF to use it. I realize these speakers are probably garbage compared to a true A/V reciever + speaker setup, but.. at $280, can't be beat I think.

So where im confused is - at this point the tech is such that there is NO way to get Dolby TrueHD or DTS HD sound out of my blu ray and go to my sound card, then even use the DAC on a quality sound card (like the one on Asus Xonar HDAV) to send to analog out to the z-5500 speakers?

To be more specific, how does it work? I am under the impression that it works like this:

Blu-ray drive reads Dolby TRUEHD audio --> POWERDVD decodes audio (and video) --> Sends video to vid card and audio to sound card --> sound card DAC converts to analog signal--> out to discrete channels in 5.1 analog setup --> Amplifier obviously amplifies signal inside the receiver or powered speaker setup (in this case the logitech z-5500 speakers) --> driven to individual speakers --> to my ears.

So am I wrong in following how this process works? As long as I have a sound card that can read the signal, in Dolby TrueHD's case its 24bit/192khz sampling, wouldn't I be hearing the signal in Dolby TrueHD? Apparently I am completely wrong about this somewhere a long the line, but I don't know where.

One final thing im really confused about is: if I had the Xonar HDAV sound card.. would the Dolby TrueHD signal be decoded on it, or is this actually done by powerdvd? This is where i'm mostly confused!

Thanks in advance again sir!

Again, I appreciate your clarification
 

s44

Diamond Member
Oct 13, 2006
9,427
16
81
Well, if you use the Logitech then lossless digital sound won't matter anyway. Remember, lossless digital is HDMI only, and requires a receiver/pre-pro that has an HDMI input. The Logitech has the pre-pro/amp stages built in, but doesn't take HDMI.

That said, you have two options. First, you can use optical. This will *only* enable standard DD/DTS sound -- not the lossless variants. Second, you can use an analog connection (the Logitech has three stereo inputs on the back that can be Y-cabled to 5.1 analog).

Originally posted by: LxMxFxD4
Blu-ray drive reads Dolby TRUEHD audio --> POWERDVD decodes audio (and video) --> Sends video to vid card and audio to sound card --> sound card DAC converts to analog signal--> out to discrete channels in 5.1 analog setup --> Amplifier obviously amplifies signal inside the receiver or powered speaker setup (in this case the logitech z-5500 speakers) --> driven to individual speakers --> to my ears.
This is correct. As I said in #9, analog works. The question is, what signal are you getting from PowerDVD's decoding?

Unfortunately, the Protected Audio Path rules apply to analog as well. Now some analog solutions *do* have a PAP, just like that S3 HDMI card does. Unfortunately (and I just looked it up), the same stupidity in the software that prevent it from recognizing the S3's PAP apply on the analog side, too. In other words:

current Blu-Ray software players will downsample HD audio to 16-bit/48khz *no matter what*

However, I should tell you something... With the Logitech as your speaker setup, there is a zero percent chance that you will notice the downsampling. In fact, I'm not even sure you'll notice the difference between lossless over analog and lossy over SPDIF.

Originally posted by: LxMxFxD4
One final thing im really confused about is: if I had the Xonar HDAV sound card.. would the Dolby TrueHD signal be decoded on it, or is this actually done by powerdvd?
The Xonar apparently comes with a proprietary version of Arcsoft's Total Media Theatre which some claim is free from downsampling.

It's still not worth your money...
 

LxMxFxD4

Senior member
Oct 6, 2007
359
0
0
Originally posted by: s44
Well, if you use the Logitech then lossless digital sound won't matter anyway. Remember, lossless digital is HDMI only, and requires a receiver/pre-pro that has an HDMI input. The Logitech has the pre-pro/amp stages built in, but doesn't take HDMI.

That said, you have two options. First, you can use optical. This will *only* enable standard DD/DTS sound -- not the lossless variants. Second, you can use an analog connection (the Logitech has three stereo inputs on the back that can be Y-cabled to 5.1 analog).

Originally posted by: LxMxFxD4
Blu-ray drive reads Dolby TRUEHD audio --> POWERDVD decodes audio (and video) --> Sends video to vid card and audio to sound card --> sound card DAC converts to analog signal--> out to discrete channels in 5.1 analog setup --> Amplifier obviously amplifies signal inside the receiver or powered speaker setup (in this case the logitech z-5500 speakers) --> driven to individual speakers --> to my ears.
This is correct. As I said in #9, analog works. The question is, what signal are you getting from PowerDVD's decoding?

Unfortunately, the Protected Audio Path rules apply to analog as well. Now some analog solutions *do* have a PAP, just like that S3 HDMI card does. Unfortunately (and I just looked it up), the same stupidity in the software that prevent it from recognizing the S3's PAP apply on the analog side, too. In other words:

current Blu-Ray software players will downsample HD audio to 16-bit/48khz *no matter what*

However, I should tell you something... With the Logitech as your speaker setup, there is a zero percent chance that you will notice the downsampling. In fact, I'm not even sure you'll notice the difference between lossless over analog and lossy over SPDIF.

Originally posted by: LxMxFxD4
One final thing im really confused about is: if I had the Xonar HDAV sound card.. would the Dolby TrueHD signal be decoded on it, or is this actually done by powerdvd?
The Xonar apparently comes with a proprietary version of Arcsoft's Total Media Theatre which some claim is free from downsampling.

It's still not worth your money...

Oh what a sad day, having learned this. I will admit that this has been a learnign experience.. and all this probably for no real productive purpose. Will I actually be able to hear the differenc between Dolby TrueHD and Dolby 5.1 on a $280 speaker setup? Answer is probably unlikely. But who knows.. i've *NEVER* heard dolby TrueHD to know!

So i'm posting all this for one final thought... given the current tech, is there a sound card that would be good for my needs or should I just do S/PDIF pass thru on my current sound card to the onboard logitech decoder that will downsample it to DTS or Dolby 5.1 as per the source?

In other words, given that i'll use the logitech z-5500 speakers, is my current sound card the best I can do or is there actually a superior sound card for this? You konw, since i'll just be passing it thru and such, i assume.

Thanks again!

 

s44

Diamond Member
Oct 13, 2006
9,427
16
81
Don't get me wrong. I was just saying that you won't be able to hear the difference between 24 bit lossless and downsampled 16 bit lossless: downsampled lossless should still be better than regular lossy DD/DTS. Better by enough to make it worth dealing with the analog noise floor, possible non-compensation of the -10db LFE, etc? I dunno. It would be easier if you had an HDMI receiver. You should at least try both connections for comparison, though.

Digital is digital, I suspect there won't be a difference between sources if you use SPDIF (in fact, for video playback you might as well use the output on your motherboard). If you use analog, you may be able to get a better card, but I don't know much about which.
 

LxMxFxD4

Senior member
Oct 6, 2007
359
0
0
Originally posted by: s44
Don't get me wrong. I was just saying that you won't be able to hear the difference between 24 bit lossless and downsampled 16 bit lossless: downsampled lossless should still be better than regular lossy DD/DTS. Better by enough to make it worth dealing with the analog noise floor, possible non-compensation of the -10db LFE, etc? I dunno. It would be easier if you had an HDMI receiver.

Digital is digital, I suspect there won't be a difference between sources if you use SPDIF (in fact, for video playback you might as well use the output on your motherboard). If you use analog, you may be able to get a better card, but I don't know much about which.

Okay, you really think that the 16bit/48khz downsample sent to soundcard then converted via that soundcard's DAC would be better than the DTS/DD5.1 pass thru via S/PDIF? Hmmm.

Then the question becomes which sound card has the best DAC right, assuming the card naturally has 16bit/48khz capability. I want to confirm that I would not actually NEED the Asus Xonar HDAV sound card - since powerDVD will supposedly be sending the True DolbyHD or DTSHD right? Or would I actually need the Xonar HDAV to get the actual HD sound?
 

s44

Diamond Member
Oct 13, 2006
9,427
16
81
The software player would decode TrueHD or DTS-MA to 5.1/7.1 PCM, which is what's in a WAV or CD track. The card itself would only have to deal with PCM decoding, which is exactly what they're all dsigned to do.

You only need the Xonar if you want to fool around with that attempt to circumvent downsampling.
 

LxMxFxD4

Senior member
Oct 6, 2007
359
0
0
Originally posted by: s44
The software player would decode TrueHD or DTS-MA to 5.1/7.1 PCM, which is what's in a WAV or CD track. The card itself would only have to deal with PCM decoding, which is exactly what they're all dsigned to do.

You only need the Xonar if you want to fool around with that attempt to circumvent downsampling.

Well thanks agian sir. I had to go to bed.

Anyone got any recs on a good (and perhaps cheap?) soundcard with a really quality DAC on all 3 analog outputs?

Thanks!
 

Spicedaddy

Platinum Member
Apr 18, 2002
2,305
77
91
I will probably get the Logitech z-5500 speakers

Okay, you really think that the 16bit/48khz downsample sent to soundcard then converted via that soundcard's DAC would be better than the DTS/DD5.1 pass thru via S/PDIF? Hmmm.


I wouldn't bother with those speakers... Just use the optical output on your current sound card to passthrough DTS or DD to the speakers.

 

LxMxFxD4

Senior member
Oct 6, 2007
359
0
0
Originally posted by: Spicedaddy
I will probably get the Logitech z-5500 speakers

Okay, you really think that the 16bit/48khz downsample sent to soundcard then converted via that soundcard's DAC would be better than the DTS/DD5.1 pass thru via S/PDIF? Hmmm.


I wouldn't bother with those speakers... Just use the optical output on your current sound card to passthrough DTS or DD to the speakers.

I appreciate your effort but if you had actually read the posts it was determined that analog out would be superior to S/PDIF for my needs. Thus the wish for a SC with a great DAC.

ANyone else?

 

erwos

Diamond Member
Apr 7, 2005
4,778
0
76
Originally posted by: LxMxFxD4
Originally posted by: Spicedaddy
I will probably get the Logitech z-5500 speakers

Okay, you really think that the 16bit/48khz downsample sent to soundcard then converted via that soundcard's DAC would be better than the DTS/DD5.1 pass thru via S/PDIF? Hmmm.


I wouldn't bother with those speakers... Just use the optical output on your current sound card to passthrough DTS or DD to the speakers.

I appreciate your effort but if you had actually read the posts it was determined that analog out would be superior to S/PDIF for my needs. Thus the wish for a SC with a great DAC.

Anyone else?
You're getting some computer speakers. The Z-5500s are reasonable as such, but pretending like you need "OMG GREAT DACS" for them is a bit of a laugh. I agree with the crowd, just go with SPDIF and save yourself the hassle of running a ton of wires.

Your speakers are going to be the limiting factor here...
 

jacc1234

Senior member
Sep 3, 2005
392
0
0
There would be NO reason you would need to worry about outputting analog vs digital with your current speakers. The only exception is if the Logitech system does a horrible job at decoding. What you should be worrying about is making sure you will be able to output a bit perfect AC3/DTS audio stream, which the chaintec will do with 3rd party drivers. I use a similar setup with my HTPC and a speaker system that is considerably "higher end" and everything sounds great. To really increase sound quality you will need to invest in better speakers. With the new lossless codecs you are approaching an area where the differences between it and the core lossy audio are not very drastic on the best speaker system. There is a difference but it is not the same as going from SD video to HD video. When it comes to HTPC's and home theater in general you have to pick your battles. There are always going to be issues with your setup and you will always be making compromises.
 

Spicedaddy

Platinum Member
Apr 18, 2002
2,305
77
91
Originally posted by: LxMxFxD4
Originally posted by: Spicedaddy
I will probably get the Logitech z-5500 speakers

Okay, you really think that the 16bit/48khz downsample sent to soundcard then converted via that soundcard's DAC would be better than the DTS/DD5.1 pass thru via S/PDIF? Hmmm.


I wouldn't bother with those speakers... Just use the optical output on your current sound card to passthrough DTS or DD to the speakers.

I appreciate your effort but if you had actually read the posts it was determined that analog out would be superior to S/PDIF for my needs. Thus the wish for a SC with a great DAC.

ANyone else?


I read the posts, did you? ;) Anyways, it's your money...