MOTU 828x 28x30 Audio Interface with ThunderTechnology - Manual (Page 64)

R E D U C I N G M O N I T O R I N G L A T E N C Y
64
Lower latency versus higher CPU overhead
The buffer setting has a large impact on the
following things:
■
Patch thru latency
■ The load on your computer’s CPU
■
Possible distortion at the smallest settings
■
How responsive the transport controls are in
your audio software
The buffer setting presents you with a trade-off
between the processing power of your computer
and the delay of live audio as it is being patched
through your software. If you reduce the size, you
reduce patch thru latency, but significantly increase
the overall processing load on your computer,
leaving less CPU bandwidth for things like real-
time effects processing. On the other hand, if you
increase the buffer size, you reduce the load on
your computer, freeing up bandwidth for effects,
mixing and other real-time operations.
If you are at a point in your recording project where
you are not currently working with live, patched-
thru material (e.g. you’re not recording vocals), or
if you have a way of externally processing inputs,
choose a higher buffer size. Depending on your
computer’s CPU speed, you might find that settings
in the middle work best (256 to 1024).
Transport responsiveness
Buffer size also impacts how quickly your audio
software will respond when you begin playback,
although not by amounts that are very noticeable.
Lowering the buffer size will make your software
respond faster; raising the buffer size will make it a
little bit slower, but barely enough to notice.
Effects processing and automated mixing
Reducing latency with the buffer size setting has
another benefit: it lets you route live inputs through
the real-time effects processing and mix
automation of your audio software.
CUEMIX FX HARDWARE MONITORING
The 828x has a more direct method of patching
audio through the system:
CueMix FX . CueMix FX
is a digital mixer in the 828x hardware itself.
CueMix FX has two important benefits:
■
First, it completely eliminates the patch thru
delay (reducing it to a small number of samples —
about the same amount as one of today’s digital
mixers).
■
Secondly, CueMix FX imposes no strain on the
computer.
The trade-off, however, is that CueMix FX
bypasses your host audio software. Instead, live
audio inputs are patched directly through to
outputs in the 828x itself and are mixed with audio
playback from your host audio software. This
means that you cannot apply host-based plug-ins,
mix automation, or other real-time effects that
your audio software provides. But for inputs that
don’t need these types of features, CueMix FX is
the way to go.
On the other hand, if you really need to use the
mixing and processing provided by your audio
software, you should not use CueMix FX. Instead,
reduce latency with the buffer setting (as explained
earlier in this chapter).
TWO METHODS FOR CONTROLLING
CUEMIX FX
There are two ways to control CueMix FX:
■
With the 828x’s CueMix FX software
■
From within your host audio software (if it
supports direct hardware monitoring)
You can even use both methods simultaneously.