SPDIF

This is the digital out of the soundcard.

More about SPDIF

Speaker setup

Configure is disabled here as the audio is send straight to the DAC.

Not to be mistaken for unaltered.

Properties

General

Not mucht to configure here.

The Properties button gives information about the driver.

I use the standard Windows HD drivers.

Formats

Check the sample rates supported by your DAC.

If you play audio with a sample rate not supported by your DAC, the Windows audio engine will do the sample rate conversion.
If you have an upsampling DAC you can use this settings to compare the SRC by Windows and your DAC. Assuming Redbook audio (44.1,) uncheck all but 44.1 and the DAC will do the upsampling.
Uncheck all but the highest input of the DAC and Windows will do the upsampling.

Level

In general it is recommended to set both volume and balance to 100 to avoid any impact of the digital volume control.

Enhancements

I belong to those silly purist who think the greatest enhancement is to disable them all.

Advanced

 

The Default Format is the one used by Windows in shared mode.

The audio engine will mix and resample all the streams to the rate set in this panel.

24 bits: my DAC is 24 bit.

Playing 16 bit using this setting won’t do any harm  as simply 8 zero’s are padded.

I set the sample rate to CD quality as almost all of my audio is 44.1 kHz.

 

Allow applications to take exclusive control should be checked if you plan to use WASAPI.
Give exclusive mode applications priority might save you a couple of drop outs.

WASAPI

WASAPI is Microsoft’s own ASIO, it talks straight to the soundcard if set to exclusive mode.
In shared mode it still uses the windows audio engine.

WASAPI in exclusive mode allows you to play all audio at its native sample rate (if your audio device supports this rate, if not it is silence).

In exclusive mode it bypasses the Windows audio engine entirely, no mixing and no resampling will take place.

As a consequence, only 1 and only 1 audio stream is playing.

Another consequence is that what the media player is sending to the soundcard must exactly match the capabilities of the sound card.

You must configure your media player to use WASAPI in exclusive mode.
The settings are media player dependent.
Crucial is that you match the bit depth.

16 or 24 depending on the capabilities of the DAC.
If you play 16 bits audio (CD) on a 24 DAC using WASAPI, the media player will append 8 zero's to get the required number of bits.
This won't affect sound quality.
In fact, there is a benefit, you can probably use digital volume control without noticeable impact on sound quality.