Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[DoubtingThomas]

I've enabled WASAPI with my new win7 system in MediaCenter.

I configured it as the dialogs told me to, resampling to 48k.

Since cd's are sampled at 44k, is resampling a good thing or does it adversely affect the sound quality?

I have a coax digital connection from my sound card to my audio system.

[jmone]

Unless there is a particular reason you want to (eg HW Compatibility) I would not resample.

[DoubtingThomas]

Does MC or WASAPI require resampling?  MC wouldn't play any files using WASAPI until I configured it as the dialog said to, to resample.

[Matt]

Does MC or WASAPI require resampling?  MC wouldn't play any files using WASAPI until I configured it as the dialog said to, to resample.

If you use WASAPI exclusive mode (an options on Media Center's WASAPI configuration dialog), you can only play sample rates natively supported by the hardware.

Normally Windows itself (or the driver) resamples to a sample rate your sound card can support.  With exclusive communication (WASAPI, ASIO, Kernel Steraming), this manipulation is disabled.*

It's actually a good thing that external processing is disabled because Media Center has a higher quality resampler and audio chain.


* This actually depends on the hardware.  Some hardware is aggressive about also applying its own processing.  Normally it can be disabled in the sound card's control panels.

[DoubtingThomas]

Matt,

I use WASAPI in non-exclusive mode since I have other programs that I use that send audio to my audio system at the same time as MC is in use (home automation stuff...).

I'm not an expert on sound processing and I didn't fully understand your reply (sorry).

Given that my hardware does support WASAPI and I will run it in non-exclusive mode, and MC requires that I resample to 48k, is WASAPI the best choice for me to be using?  Or is the resampling a good thing in this case?

I am not using any DAC's in my sound card, I use a digital coax connection to my audio system.

[Vincent Kars]

This is the architecture of Win7 audio

As you can see all output is routed trough the audio engine wit one exception: WASAPI in exclusive mode. The audio engine is the one doing the mixing, re-sampling, etc.
Using exclusive mode can improve the sound quality but it looks like your hard ware can only play 48 and not 44.1, the native sample rate of CD’s.
You might try WASAPI in exclusive mode, no SRC will be supplied.
If this fails it is probably because your hard ware don’t support 44.1
You might try WASAPI non exclusive using the SRC of J River or DS (Direct Sound, Win7 default)  and check if you hear any difference.
If not I recommend DS for a hassle free experience

[DoubtingThomas]

Vincent, thanks for the reply.

I swapped from using the motherboard sound to my other card and now I can get WASAPI to run at 44.1k without resampling.  Thanks!