An introduction to computer audio
I use Windows 7 Ultimate NL with the English language pack.
But sometimes things are not translated like ‘Luidspreker’ (Loudspeaker of course).
I set the onboard speakers to default and mute the speaker.
In the media player I select the outboard DAC.
As all other applications use the default playback device, no more system sounds at full blast over the audio!
In the Sound panel, choose your playback device and click Configure.
The options available depend on the capabilities of the playback device
Check if the channels matches your setup.
Test if speakers and the channels match by clicking the speaker icons.
In this case (onboard speakers) I leave Full Range unchecked.
If you are using external full-range speakers, check Full-range otherwise you get a rather funny sound out of them.
The general tab allows you to change the description and the icon.
Benchmark icons (and a lot more) by Zelak
No, changing the Icon into a very prestigious DAC won't affect sound quality.
You can put it off in case you don't like a full blast e-mail notification over your stereo.
Often you have more than one playback device.
If your media players has the option to select an output device other than system default you can do the following.
Set the system default to the onboard speakers.
Mute them if needed.
In your media player select your audio device
Now all sounds of any program go to the onboard speakers except the output of the media player.
Properties in this tab gives you information about the driver.
Often a third party driver comes with your sound card.
It might be that this driver is not an improvement as far as sound quality is concerned, compared with the default Win7 HD audio driver.
A simple way to try:
You can adjust volume and the balance.
If you prefer analogue volume control, set both volume and balance to 100 to eliminate any impact of the digital volume control.
I belong to those silly purist who think the greatest enhancement is to disable them all.
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 zeroes 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 dropouts.
Sample rate conversion might affect sound quality.
When you convert the sample rate of an audio file from one frequency to another frequency on a computer that is running Windows 7 or Windows Server 2008 R2, the new audio file sounds distorted during playback.
The audio file sounds distorted when you play it on any audio record, capture, or encoder application if the following conditions are true:
By design all audio is resampled to the Default Format as specified here.
If the source sample rate matches this setting, you expect a bit perfect stream.
This is not the case.
Q: If you
•don't apply any per-stream or global effects and
•only have one application outputting audio and
•the sample rate and bit-depth set for the sound card matches the material's sample rate
then there should theoretically be no difference to the original because a conversion from even 24-bit integer to 32-bit float is lossless.
A: Not quite. Since we can not assure that there was nothing added, no gain controls changed, etc, we must dither the final float->fix conversion, so you will incur one step of dithering at your card's level. As annoying as this is for gain=1 with single sources, we can't possibly single-source in general.
If you don't want even that, there is exclusive mode, which is roughly speaking a memcopy.
J. D. (jj) Johnston
WASAPI is Microsoft’s own ASIO, it talks straight to the soundcard if set to exclusive mode.
As it is exclusive mode, no other application can use the sound card.
No more system sounds at full blast over the stereo!
As WASAPI in exclusive mode talks straight to the driver of the audio device, the stream send to this device must match the capabilities of this device in terms of bit depth, sample rate, number of channels and audio format (PCM most of the time) otherwise it is silence.
The program using WASAPI can do this by configuring the audio device to match the source.
In this case we have bit perfect playback.
This allows for automatic sample rate switching as well.
The developer can also choose to adept the source to the capabilities of the audio device.
If the source is mono and the audio device 2 channel, the developer might decide to send the same signal to both channels.
If the sample rate of the source is not supported by the hardware e.g. 192 kHz source with a 96 kHz audio device, the program using WASAPI has to do the SRC (Sample Rate Conversion).
Check if the SRC implemented by this program is an improvement compared with the SRC provided by Windows because writing a good SRC is not trivial.
Obvious using WASAPI in exclusive mode doesn’t guarantee bit perfect playback.
It is up to the developer of the media player using WASAPI to see to it that the playback is bit perfect.
Bit perfect playback is impossible by design if de properties of the audio file e.g. sample rate are not supported by the hardware.