Windows XP k mixer vs. whatever is in Vista Options

[audiophilosophy]

I'm a noob with this technical sort of stuff, but I was wondering if the audio processing stuff included in Vista is better or worse than what we had with XP.

Ok, since I am a noob, this is what I have gathered about XP's audio processing--- the k mixer is bad, and it has a degrading effect on the sound unless you decided to take steps to entirely bypass the k mixer. Correct me if I'm wrong about this.

So I'm wondering, are there any improvements over XP's k mixer with what comes standard with Vista?

[AndyH-ha]

so obviously kmixer changes digital stream in some way

But the change that quashes DTS doesn't have t9o be great enough to be perceived with regular stereo material.

[Dogbert]

so obviously kmixer changes digital stream in some way

But the change that quashes DTS doesn't have t9o be great enough to be perceived with regular stereo material.

Contrary to popular belief, the kmixer of XP and 2k doesn't change a thing when you move the wave volume slider to the max. DTS encoded wave files can be played through WaveOut/DSound and through the kernel mixer without any loss.

And I should know, I've developed a driver for the C-Media 8738/8768 which just can do that stunt.

The mixing engine of Vista works with 32bit float samples, so there's actually some information lost in the conversion. But there is a so called "exclusive mode" which is available through the WASAPI. It should give you bitperfect output, albeit I haven't seen software which actually support it (yet).

[crni]

Contrary to popular belief, the kmixer of XP and 2k doesn't change a thing when you move the wave volume slider to the max. DTS encoded wave files can be played through WaveOut/DSound and through the kernel mixer without any loss.

Unfortunately that is not case with my card, even with volume slider(s) maxed out in mixer when using DSound in foobar receiver doesn't pick up DTS signal. It briefly switches to DTS but apparently signal is 'week' and receiver reverts back to hissing instantly so IMHO 'contrary to popular belief' kmixer does change signal. It's true that it doesn't effects PCM 44.1 signal but it surely 'destroys' DTS 44.1 stream (at least im my case).
ONLY way I can get unchanged DTS signal to my receiver is when bypassing kmixer via ASIO or KS plugin.

[Dogbert]

ONLY way I can get unchanged DTS signal to my receiver is when bypassing kmixer via ASIO or KS plugin.

That's the driver then which modifies the data in one way or the other, not the kernel mixer. Like I said, under the conditions that the Wave Volume is maxed out and that no other stream is playing, bitperfect output is possible under XP and 2k using WaveOut/DSound.

So are you saying that the audio quality that comes standard for XP is superior to what comes standard for Vista?

No, it's not that easy. For instance, if the kernel mixer of 2k/XP mixes two loud streams, it's much more prone to nasty clipping due to the limitations of the 16bit format. That won't happen in Vista.
But like I said, it is impossible (or I haven't found a way yet) to forward a regular wave stream bitperfectly to the receiver through DirectSound/WaveOut in Vista.

Drivers which are built around the WaveCyclic/WavePCI model can still be used for kernel streaming in Vista, but if you have to use a WaveRT driver, you'll have to wait for WASAPI support to get bitperfect playback in Vista.

This post has been edited by Dogbert: Feb 4 2007, 17:29

[audiophilosophy]

But like I said, it is impossible (or I haven't found a way yet) to forward a regular wave stream bitperfectly to the receiver through DirectSound/WaveOut.

you mean just in Vista, right? Becaues just before that you said that in XP you could get bit perfect through DirectSound/WaveOut