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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.
Figure 4-2: In Digital Performer and Performer Lite, choose Setup
menu> Configure Audio System> Configure Hardware Driver to open
the dialog shown above and access the Buffer Size setting.
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.
Adjusting buffer size on Windows
On Windows, the buffer size is adjusted in the
M Series control panel (page 12). Also see “Buffer
Size”.
Lower latency versus higher CPU overhead
Buffer size has a large impact on the following:
Q Monitoring latency
Q The load on your computer’s CPU
Q Responsiveness of transport controls and effect
knobs in Performer Lite or other audio software.
LOOPBACK
Use the Loopback 1-2 input channels provided by
the M Series audio driver to capture audio output
from your computer. These channels return the
signal being sent to Outputs 1-2 back to the
computer, as Loopback inputs 1-2, so that you can
capture the signal in your host software, stream it
to the web or broadcast it with pod casting
software.
Q Real-time virtual instrument latency.
Mixing loopback with live inputs
If you need to mix loopback channels with live
inputs, use the Loopback 1-2 Mix channels
provided by the M Series audio driver. These
channels combine audio being sent to Outputs 1-2
from the computer with any live signals on the
unit’s inputs. For example, you could play back a
music (or other audio) from your computer
software, speak or sing into a mic connected to the
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 monitoring 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.
W O R K I N G W I T H H O S T A U D I O S O F T W A R E
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