User Manual

SOFTWARE INSTALLATION
30
AUDIO DRIVERS
The installer provides USB audio drivers for Mac
(CoreAudio) and Windows (ASIO and Wave).
Industry-leading I/O latency performance
On OS X and Windows, the MOTU Pro Audio
driver provides exceptionally low I/O latency
performance for USB operation. For example, with
a 32-sample buffer size, an LP32 interface
operating at 96 kHz produces round trip latency
(RTL) performance of 1.63 milliseconds (ms) over
USB on Windows and 1.61 ms on OS X. RTL is the
measurement of the time it takes audio to pass
from an input, through a high-performance DAW
host such as Digital Performer, to an output.
MOTU Pro Audio ASIO Driver
On Windows, to enable the LP32 in your ASIO host
software, choose the MOTU Pro Audio ASIO
driver.
Figure 3-1: Choosing the MOTU Pro Audio ASIO driver in Cubase.
WDM / Wave driver support
On Windows, the MOTU Pro Audio driver
includes stereo and multi-channel support (up to
24 channels) for WDM (Wave) compatible audio
software.
Host Buffer Size
When connected to a Windows host, the Host
Buffer Size menu (Figure 3-2) is available in the
Device tab (page 12). This setting determines the
amount of latency (delay) you may hear when live
audio is patched through your Windows audio
software. Smaller buffer sizes produce lower
latency, with sizes of 256 samples or less producing
virtually imperceptible delay. Many host
applications report audio hardware I/O latency, so
you can see what happens to the reported latency
when making adjustments to this setting.
Figure 3-2: Access the ‘Host Buffer Size’ and ‘Host Safety Offset’
settings in the web app Device tab for your MOTU interface.
Be careful with very small buffer sizes, as they can
cause performance issues from your host software
or PC.
☛ At sea level, audio travels approximately one
foot (30 cm) per millisecond. A latency of ten
milliseconds is about the same as being ten feet
(three meters) from an audio source.