Trying to understand HD audio.

wolvers69 said:
I'm no audiophile but I'll try to answer as best as I can.

If it's just into his TV I would assume that PCM would be the correct choice and probably even if it was feeding into a receiver first. You'd only set it bitstream AFAIK if you wanted to have your receiver do the decoding but as already mentioned you wouldn't get a TrueHD or DTS-HD bitstream that way from a PS3.
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Thanks mate that clears it up for me :)
 
Added information to original post on PCM output from PS3 and current known issues with the Asus HDAV card.
 
Quick Q :

i have a Sony STR-DB 1080 6.1 amp does DD an DTS .. old i know ..

now from i`ve picked up on SD DVD`s audio is ,
DTS is either 768 or 1536 kbs data rate .
DD is either 384 or 448 an sometimes 640 at a push on normal SD DVD`s

i`ve just got a new Panasonic DMP DB30 Blu Ray player .

I know my amp doesn`t support these new HD audio tracks (nxt thing on my upgrade list is a HDMI HD Amp),
but will play DD/DTS off the BR-HD disc`s i`ve bought , is this normal DD/DTS or a downmixed DD trueHD ?

also what are the data rates for DD TrueHD an DTS MA ?

what i have noticed aswell when i play a DD True HD audio track on my amp it reports the data rate at 640kbs is this right ?

also i`ve noticed that some disc`s i`ve bought it says DTS MA on them but comes up as a DD track .. very confusing :(

anyone ?
 
Another question - in the first post it says the stream gets downsampled both over hdmi from a graphics card and via analogue. How much difference does this downsampling really make? I realise it won't be "as good" as doing it the "proper" way but will it really be audibly different? Especially to a ~£400 receiver and ~£900 5.1 system?

Do TMT or windvd send a non-downsampled stream?

Also am i right in thinking the free version of powerdvd which comes with the lg combo drive won't even send an 8 channel pcm feed without buying the full version?

Thanks in advance :)
 
Mav said:
Quick Q :

i have a Sony STR-DB 1080 6.1 amp does DD an DTS .. old i know ..

now from i`ve picked up on SD DVD`s audio is ,
DTS is either 768 or 1536 kbs data rate .
DD is either 384 or 448 an sometimes 640 at a push on normal SD DVD`s

i`ve just got a new Panasonic DMP DB30 Blu Ray player .

I know my amp doesn`t support these new HD audio tracks (nxt thing on my upgrade list is a HDMI HD Amp),
but will play DD/DTS off the BR-HD disc`s i`ve bought , is this normal DD/DTS or a downmixed DD trueHD ?

also what are the data rates for DD TrueHD an DTS MA ?

what i have noticed aswell when i play a DD True HD audio track on my amp it reports the data rate at 640kbs is this right ?

also i`ve noticed that some disc`s i`ve bought it says DTS MA on them but comes up as a DD track .. very confusing :(

anyone ?
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As far as I know, both DTS-MA and Dolby True-HD include the standard DTS/Dolby Digital streams within them so that incompatible systems can play this instead. This might be what you are finding.
 
Lil old me said:
Another question - in the first post it says the stream gets downsampled both over hdmi from a graphics card and via analogue. How much difference does this downsampling really make? I realise it won't be "as good" as doing it the "proper" way but will it really be audibly different? Especially to a ~£400 receiver and ~£900 5.1 system?

Do TMT or windvd send a non-downsampled stream?

Also am i right in thinking the free version of powerdvd which comes with the lg combo drive won't even send an 8 channel pcm feed without buying the full version?

Thanks in advance :)
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This is the great debate at the moment! Lots of arguments are going around about how good ears are, how good speakers are and whether or not there is an audible difference between lossy formats (Dolby Digital/DTS), lossless formats (Dolby True HD/DTS-MA/PCM) or downsampled lossless formats.

Secondly, there does not seem to be a definitive test for whether or not the audio is downsampled and whereas Cyberlink freely admit this, Arcsoft seem a little tight-lipped about downsampling in TMT. Some believe that the analogue output in TMT is not downsampled. I'm not convinced one way or the other. It is (in my opinion) better sounding than PowerDVD through my Asus D2X/Onkyo 606/Q-Accoustics Q-AV setup.

To add to the confusion, Vista has something called "Exclusive mode" for audio and if it's not using this then the audio stream is tampered with. You can apparently tell if you can play system noises over whatever source you're playing. I don't know if this confirms downsampling or not, I think it just confirms tampering.

Most annoyingly of all, there is no good reason why lossless audio can't be output from a PC over analogue and all of this debate and frustration seems to have been caused by the (presumably mistaken) belief in Hollywood that what we all really want to do is pirate lossless audio soundtracks from movies with or without pictures.

Hope that helps!
 
Thats really great maverick thanks! Although it really opens up the debate even more which is a bit annoying!

Basically im looking to get a proper av amp for xmas and im trying to decide between the onkyo 576, 606 or the sony 820. The 576 has analogue inputs but no hd decoding, the sony has hd decoding but no analogue and the 606 has both but is £150 more than the others! And that is all academic given no solution wil transmit a proper hd stream on the pc anyway yet but i feel like itd be worth it in the future.

If there really isnt a noticable difference it makes me really wonder what the point is especially given the difference in cost.
 
One vote for Onkyo 606- remember it also has a decent upscaler built in but it doesn't go to the dizzy heights of 1080p, only 720p or 1080i. The only drawback is it gets hotter than a hot thing on a hot day!

You should also consider the Yamaha DSP-AX763 for the same money. Haven't heard one myself yet, but a lot of people are raving about it. No upscaler, but covers your analogue input and HD codec bases nicely.

Best of luck!
 
Lil old me said:
Thats really great maverick thanks! Although it really opens up the debate even more which is a bit annoying!

Basically im looking to get a proper av amp for xmas and im trying to decide between the onkyo 576, 606 or the sony 820. The 576 has analogue inputs but no hd decoding, the sony has hd decoding but no analogue and the 606 has both but is £150 more than the others! And that is all academic given no solution wil transmit a proper hd stream on the pc anyway yet but i feel like itd be worth it in the future.

If there really isnt a noticable difference it makes me really wonder what the point is especially given the difference in cost.
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Whether the HD audio sounds better or not is up for debate, although I think they sound awesome, but what they do give you that the lossy ones do not is 8 discrete channels as opposed to 6. I thought that I had put this in the first post but if not then I shall.

The Asus HDAV sound card now has drivers, and a version of TMT, available that can bitstream all of the HD audio tracks via HDMI to an av amp and output them over analogues (deluxe version). When I get time I will adjust the first post to include this info.

Also I've added a link to a good explanation of the audio formats that are on Blu-ray and HD-DVD as I see there has been some discussion on this. It's too much information for me to add here.
 
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Just as an aside;
http://www.auzentech.com/site/products/x-fi_hometheater_hd.php
is due out in January (although has been delayed before), which should be able to do the same as the HDAV, and usually has pretty decent drivers/compatibility.

I noted that they did say that Full Resolution Audio is only available on vista, I assume this is to do with the protected path stuff...

A couple of queries from me:

HD4350 - Does this do the 8 channel LPCM which the higher HD4000 series cards?
Which would sound better; a PS3 doing LPCM or an HD4000 series doing LPCM?
(I have an Onkyo 606 & Quad L-ites)

The 4350 can be had for less than £50, and does 'some gaming' as well, however I cant imagine either of the HDMI souncards getting below £100 any time soon :(.
 
wolvers69 said:
Whether the HD audio sounds better or not is up for debate, although I think they sound awesome, but what they do give you that the lossy ones do not is 8 discrete channels as opposed to 6. I thought that I had put this in the first post but if not then I shall.
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By lossy ones do you mean an analogue LPCM setup? I was under the impression that this would give 8 channels but from your post it sounds not? If analogue cant do 8 channels then would a LPCM signal through an hdmi audio enabled graphics card (thinking radeon 4xxx series here) manage it?

I wish i could afford the asus soundcard but thats not an option at the moment really.
 
Lil old me said:
By lossy ones do you mean an analogue LPCM setup?
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No I mean DD and DTS. Have you read the first post and the link I attached?

Lil old me said:
would a LPCM signal through an hdmi audio enabled graphics card (thinking radeon 4xxx series here) manage it?
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I've added another link about 8 channel LPCM to the first post. It's slightly out of date now that the HDAV exists but has a good explanation.
 
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thx wolvers69 for u`re added link for the new HD audio ...

http://www.highdefdigest.com/news/s..._FAQ:_Blu-ray_and_HD_DVD_Audio_Explained/1064

now i know what i`am looking for when i upgrade my amp in the new year , besides having HDMI connectors (at least 4 in 1 out ) an upscaling 1080p/24 i need a list as long as my arm for the audio standards , hopefully they should have come down in price a bit by then aswell ;)
 
wolvers69 said:
No I mean DD and DTS. Have you read the first post and the link I attached?

I've added another link about 8 channel LPCM to the first post. It's slightly out of date now that the HDAV exists but has a good explanation.
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Yea I had read the link, sorry I misunderstood what you meant in the post I queried. Re-reading knowing thats what you mean it makes much more sense.

I have read that article too, which is why i was querying your post because it read to the contrary but now i know what you meant it makes perfect sense now!

So overall within my budget (not being able to afford a new soundcard) but still wanting 8 channels I have two options 1 3.5mm jacks from my current soundcard to the multichannel inputs on my amp or get a new 4xxx series card and connect it via hdmi to my amp.

Both options would give me LPCM lossless 7.1 sound but downsampled by powerdvd, potentially tmt and any other software player however the difference should be minimal and not worth £180 at any rate!
 
Edited as the HDAV can now do bitstreaming of HD audio, in XP and Vista, and the new revision cards that handle 1080p24hz have gone on sale in Taiwan.

Asus are going to announce details of an RMA on current cards in January..........I hope! :rolleyes:
 
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