Standard USB sound in Vista
Mar 22, 2007 at 3:24 AM Thread Starter Post #1 of 19

bangraman

Headphoneus Supremus
Joined
Oct 3, 2002
Posts
10,278
Likes
36
I had a casual look at the new Vista audio structure, but the diagram I was looking at didn't make all that much sense to me.


I'm currently replacing all of my main PC's with Vista Business and Ultimate systems and I'd like to know whether it means that a regular USB audio device outputting digital audio (say an Audiotrak Optoplay, which is recognised and works in Vista) is bit-perfect under Vista.


It's really a point of interest for my laptop systems more than anything.
 
Mar 22, 2007 at 8:11 AM Post #2 of 19

EnOYiN

Headphoneus Supremus
Joined
Jan 13, 2007
Posts
2,269
Likes
18
For as far as I know this is not necessarily true. It still depends on what you would use. Only OpenAL and ASIO are bit-perfect for sure. For the rest it can be bit-perfect depending on what will be resampled/added within the APOs. After going through the APOs the audio-architecture will use a kernel streaming transport to get to the hardware.

For more information you can go here. This is a weblog of one of the people working on the audio-architecture of Vista.

I haven't really read up on the Vista audio-architecture yet myself so I can't really give a clear answer to this.

P.S. Are you reffering to the diagram I made (Larry Osterman originally) or to something else?
 
Mar 24, 2007 at 7:43 PM Post #5 of 19

bangraman

Headphoneus Supremus
Joined
Oct 3, 2002
Posts
10,278
Likes
36
Quote:

Originally Posted by EnOYiN /img/forum/go_quote.gif
For as far as I know this is not necessarily true. It still depends on what you would use. Only OpenAL and ASIO are bit-perfect for sure. For the rest it can be bit-perfect depending on what will be resampled/added within the APOs. After going through the APOs the audio-architecture will use a kernel streaming transport to get to the hardware.

For more information you can go here. This is a weblog of one of the people working on the audio-architecture of Vista.

I haven't really read up on the Vista audio-architecture yet myself so I can't really give a clear answer to this.

P.S. Are you reffering to the diagram I made (Larry Osterman originally) or to something else?



I don't know - it was a rather convoluted diagram, that's all I remember. I blanked out.

The blog wasn't really all that helpful I have to say. Anyone got any other ideas / resources?
 
Mar 24, 2007 at 11:02 PM Post #6 of 19

EnOYiN

Headphoneus Supremus
Joined
Jan 13, 2007
Posts
2,269
Likes
18
I read through a whole lot of text before I found out how all of this actually works. ( I was interested myself as well so that helped a lot )

You can't get bit-perfect output in Windows Vista. I looked it up from various sources. The only way to get actual bit-perfect output is to use KS or ASIO.
It was also in the blog I provided a link to before btw - just not too easy to find. Sorry for that inconvenient link.

Recommended source:
http://www.hydrogenaudio.org/forums/...dpost&p=469467

Loads of text:
http://www.avsforum.com/avs-vb/showt...3&page=1&pp=30

A test done by someone of the AVS forum:
http://archive.avsforum.com/avs-vb/s...86#post2493886

Cheers.
 
Mar 25, 2007 at 6:01 PM Post #7 of 19

bangraman

Headphoneus Supremus
Joined
Oct 3, 2002
Posts
10,278
Likes
36
Second link was very helpful - thanks. So if apps are written to support Exclusive Mode, it will be. If not then it's still resampled but you get a lot more scope in what the OS can do with the sound. I think I'm satisfied with that answer.
 
Mar 25, 2007 at 7:22 PM Post #8 of 19

EnOYiN

Headphoneus Supremus
Joined
Jan 13, 2007
Posts
2,269
Likes
18
Quote:

Originally Posted by bangraman /img/forum/go_quote.gif
Second link was very helpful - thanks. So if apps are written to support Exclusive Mode, it will be. If not then it's still resampled but you get a lot more scope in what the OS can do with the sound. I think I'm satisfied with that answer.


For as far as I understand it right now that's true indeed. The sound in Vista is a lot better using mixed sound than it was in XP.

Edit: I have been installing a few Vista computer and I noticed that there aren't a lot applications which support this audio-architecture completely. Foobar doesn't for instance.
 
Apr 28, 2007 at 8:31 PM Post #10 of 19

EnOYiN

Headphoneus Supremus
Joined
Jan 13, 2007
Posts
2,269
Likes
18
Quote:

Originally Posted by Tachikoma /img/forum/go_quote.gif
Just wondering, for USB devices that use the standard USB audio driver on vista, will they be in asynchronous mode or isochronous mode? For example, the UDA1321 chip?


"The reality: There are NO USB audio chips that out of the box support asynchronous mode!"

This is quoted straight from here.
 
Apr 29, 2007 at 7:43 AM Post #11 of 19

Tachikoma

Headphoneus Supremus
Joined
Jul 19, 2005
Posts
2,067
Likes
119
Quote:

The UDA1321 is an adaptive asynchronous sink USB audio device with a continuous sampling frequency (fs) range from 5 to 55 kHz.


Thats quoted from the UDA1321's datasheet. Isn't the main reason that there weren't any USB audio chips running in async out of the box, the fact that the windows XP usbaudio.sys file simply does not support asynchronous endpoints? (which was fixed in vista iirc)
 
Apr 29, 2007 at 11:45 AM Post #13 of 19

Riboge

500+ Head-Fier
Joined
Oct 2, 2005
Posts
627
Likes
10
I found the spdif out from the X-Fi to sound just fine running 24bit at 48 or 96kHz, so I am wondering if your driver is corrupted. I am using it with a Stereovox HVXC cable to a Bel Canto dac 3, playing foobar.
 
Apr 29, 2007 at 12:00 PM Post #14 of 19

maarek99

1000+ Head-Fier
Joined
Aug 24, 2004
Posts
1,086
Likes
15
It works fine if I use the spdif out-playback device. When utilising the speakers out (so I get both speakers and spdif) the output sounds heavily processed, no matter what options I set.
 
May 1, 2007 at 9:56 AM Post #15 of 19

Toby M

100+ Head-Fier
Joined
May 9, 2005
Posts
160
Likes
1
Quote:

Originally Posted by maarek99 /img/forum/go_quote.gif
It works fine if I use the spdif out-playback device. When utilising the speakers out (so I get both speakers and spdif) the output sounds heavily processed, no matter what options I set.


Have you got that cmss 3d crap turned off in the driver? The Vista64 driver for the Audigy 2 turns it on by default so I guess the X-fi driver does the same thing. Took me like a week to work it out since in XP it was off by default.
 

Users who are viewing this thread

Top