Hi,

Quick question for the DAW/OS experts:  If the same hardware & software (drivers and Sonar) were installed on two identical machines, the only difference being one had W2K and the other XP, would there be a sound difference?  More specifically I'm wondering if the two different OS's might do anything internal to the audio path to alter the bit stream.  For the purpose of this question I'm only concerned about audio quality not minor latency differences.   I've tried to poke around on this subject and am getting a lot of conflicting information, some folks say there is an audio stack and/or OS "mixer" driver that alters the bit stream, etc.  Not really sure what to believe....
 
(In case it matters we are talking about RME Fireface and their WDM drivers)

Thanks,
 
    Sonic

As someone who has come from Win 98 to Win XP and now Win 7 I must say I am not hearing any major differences at all.  In some case projects were migrated over the OS systems and still no major difference either.  If they are handling audio differently then I am certainly not hearing it.  In any major way that is.
 
I also run Studio One on a Win 7 machine and an iMac and also not hearing any differences either.  Not only with the same interface on either but even with different interfaces being involved.
 
That is the cool thing about digital.  It has amazing uniform consistency.  Unlike playing back the same 2" reel to reel multitrack on a raft of different machines and through totally different mixing consoles. That represents the opposite. 
 
I think you may be suffering from a dose of mis information on the net syndrome.  There are far more important things that are going to influence the quality of your production. 

Definitely NO.
Because we digitize and restore for a lot of publishers in "highest quality", this is asked again and again. And therefor we have tested and made checks with SONAR constantly.
It does not matter which DAW or OS you use. It does not matter if you use ASIO or WDM. In the worst case you may have problems with latency or stability.
The quality depends - ONLY - on what audiointerface you use for recording. We use RME, also Roland and Focusrite which are very good.
By exporting a file to disc, the audiointerface does not matter.
 

By exporting a file to disc, the audiointerface does not matter.
 
+1 

Thanks for the fast and helpful responses.  
Does the same thing hold for real-time playback (mixing) as well?
Sonic

Yes. The defining element is the D/A conversion. If you're using the same interface, the waveforms are the same.
 

Jeffvans
I think you may be suffering from a dose of mis information on the net syndrome.  There are far more important things that are going to influence the quality of your production.

 
Agreed.

The answer to the title question is a resounding NO.