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In detail - special properties of the drivers.
The following contains in-depth information for those with the need to know. Less
experienced users won't encounter any problems if they skip over this section.
32-bit data transfer.
The drivers support a special data transfer format known as "32-bit unpacked". Audio
data streams are transferred to the computer's main memory via the PCI bus. The PCI
bus features 32 "lines" (32-bit). A Computer generally takes care to ensure that its data
lines are well-utilized. For this reason, 8-bit audio data is always sent on its way in groups
of four packets (4 x 8 = 32), and 16-bit data (2 x 16 = 32) in groups of two (top of
diagram).
The situation is a bit more complicated from the processing standpoint with 24-bit audio
data: suddenly there's "only" 24 sweet-sounding bits available, i.e. 8 bits are "missing".
The "24-bit packed" process solves this problem in the following manner: the computer
CPU (your Pentium, for example) divides the 24-bit data into multiples of 32 (middle of
diagram). That costs computing power and isn't really necessary.
The "32-bit unpacked" process fills the remaining bits with zeroes and the driver sends
suitable 32-bit packets on their merry way. Most commonly-used applications currently
support this process, which is particularly easy on the computer's resources (bottom of
diagram).
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. WDM (Windows Driver Model) is a recent driver concept
from that popular Redmond-based software manufacturer which also involves a number
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PHASE 28 (English)
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