TerraTec PHASE 26 USB, Руководство пользователя

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In detail - special properties of the drivers.
DirectSound & WDM.
It goes without saying that the drivers of the PHASE system also support Microsoft's
DirectSound or DirectSound 3D interface. What's more, the software complies strictly with
Microsoft's WDM specification. For example, the drivers are able to play back audio data
streams from multiple applications in parallel (multi-client, a “luxury” that faithful TerraTec
customers have enjoyed since 1997).
WDM sample rate (SR) interpolation.
The multi-client capability of the WDM architecture also permits the simultaneous
playback of multiple audio data streams with differing sample rates. The sampler fre-
quency used for all streams is based on the file called up first. All further data streams -
those called up during the run time of the first file - are interpolated as required and their
pitch is not affected.
An SR conversion/interpolation does always result in a certain loss of quality,
however.
You should therefore ensure that you do not use several programs simultane-
ously with differing sample rates for applications in which the highest possible audio
quality is vital. For example, it's best to only have the playback software running when
transferring a piece of music at 44.1 kHz to a DAT recorder.
WDM kernel streaming.
WDM kernel streaming also represents a new technology for Microsoft. Like already
established models such as Steinberg's ASIO interface, kernel streaming permits
extremely fast access to the audio hardware. The deployed software (such as audio/MIDI
sequencers or software synthesizers) must support the WDM function directly, however.
One of these programs, for example, is the “Sonar” recording software produced by the
Cakewalk company.
32 PHASE 26 USB (English)