Cambridge Audio DacMagic Plus User Manual download pdf (Page 24)

Bit perfect transfer – ASIO and WASAPI Exclusive mode

The DacMagic Plus USB interface hardware and software support bit perfect transfer.

Whether or not the audio sent to the DacMagic Plus is bitperfect (i.e. not resampled or mixed etc. by the

PC) is actually a function of the playback application and the operating systems audio engine.

By default the standard windows audio drivers (often called WDM drivers) included in Windows XP

support MME or DirectSound transfer, both of which include a kernel mixer and re-sampler stage.

One way round this is to use ASIO to bypass this. Another is to use a playback application that

supports its own form of kernel streaming, i.e. if has its own way of outputting the audio without

invoking the kernel mixer.

For Windows Vista and Windows 7 a new method of audio transfer is supported called WASAPI.

This has two modes; Shared and Exclusive. Shared mode is similar to MME or DirectSound but in

Exclusive mode the kernel mixer/re-sampler is bypassed and bit perfect transfer is possible with

only one audio playback program directed to the soundcard at a time (for instance system sounds

are not mixed in).

To ensure bit perfect transfer use a playback application that supports ASIO, WASAPI in Exclusive

mode (if you have Windows Vista or Windows 7) or some form of kernel streaming.

This is a fast moving area so we would encourage you to check the web for the latest media players

to support these more audiophile playback options.

To use ASIO you will need the Cambridge Audio Sound Driver installed and the DacMagic Plus switched

to USB Audio 2.0.

No further settings are required as the driver automatically supports ASIO transfer, all that is required

is to load and setup suitable ASIO enabled playback software.

ASIO (Audio Stream Input/Output) is a non Microsoft audio driver protocol for Windows originally

invented by Steinberg ltd ASIO bypasses some of the normal audio path from the playback

application through the Windows audio system (including the Kernel Mixer) for a more direct path

to the DacMagic Plus.

You will need to install and use a suitable playback application that supports ASIO output either

natively or via a plugin. One example of such an application with a suitable plugin is Foobar, see

http://www.foobar2000.org for more details.

1 2 ... 19 20 21 22 23 24 25 26 27 28 29 ... 39 40

No comments

Cambridge Audio DacMagic Plus User Manual Page 24