Metric Halo 2882 operating guide - Manual (Page 77)

Mobile I/O User’s Guide
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ASIO B UFFERS
Audio channels are transported individually in buffer sized chunks. The size
of the audio buffers has an effect on the CPU load of the audio application,
as well as the round-trip latency from input to output when the audio is
routed through the host application for monitoring or processing.
Generally, the CPU load increases as the buffer size decreases (this is not
true for all hosts; emagic’s Logic Audio is a notable exception). On the other
hand, the latency decreases as the buffer size decreases.
Since, in general, you want the lowest CPU load and the lowest latency, you
will have to make trade-offs.
The WIDE mixer engine in Mobile I/O helps substantially with this issue,
because for the common critical monitoring configuration (monitoring while
tracking external sources), the Mobile I/O mixer removes all of the ASIO
latency from the monitor path and allows you to decouple the latency from
the buffer size.
In the case that you are trying to perform with a softsynth running in your
host, Mobile I/O’s mixer does not help decrease the latency since the signal
is being generated on the computer. In this case you’ll want to minimize the
output latency by selecting the smallest ASIO buffer size possible. This will
depend on your computer hardware, the amount of processing you are
doing, and the ASIO host you use.
S ETTING THE ASIO B UFFER S IZE
The methods used to set the ASIO buffer size will vary from host to host.
Some ASIO hosts provide direct controls for adjusting the buffer size and
others do not. If your host supports setting the buffer size directly, you
should take advantage of that facility. Most hosts that support controlling the
buffer size will automatically save your selected buffer size with your ses-
sion.
Mobile I/O supports buffer sizes that are powers-of-two. This means that you
can use buffers that are 64, 128, 256, 512, 1024, or 2048 samples long.
Some hosts that allow you to change the buffer size do not properly follow
the ASIO spec and will let you specify buffer sizes that are not supported by