M-Audio FireWire 1814, Руководство пользователя

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Sample Rate Detected – This field displays the detected sample rate that is being
received from the currently selected sync source. When the sync source is set to
internal , the FireWire 1814 will detect and display the sampling rate as set by your
audio software or your computer’s operating system via the IEEE 1394 (FireWire) bus.
When the sync source is set to any of the
external sync choices, the FireWire 1814 will
detect and display the sampling rate that is being received at the selected sync input.
NOTE: When you are using the FireWire 1814 at a sample rate of either 88.2kHz or
96kHz in conjunction with the optical port being set for adat operation, you must enable
the “adat S/MUX” checkbox found in the lower left of the hardware page (some
applications may set this automatically). In S/MUX mode, ADAT Optical switches from 8-
channel operation to 4-channel operation. Not all external ADAT Optical-capable devices
can operate in S/MUX mode, so be sure and check your device’s documentation for
more information.
ASIO/WDM Buffer Size – In this field you can select the buffer size you wish to work
with. Smaller buffer sizes result in lower latency (the time it takes for your input signal to
pass through your audio software and appear at the outputs), but may not function well
with slower systems. The default buffer size setting is 256. This setting may adequately
serve your purposes, but you can experiment with lower settings if you wish. If you
experience stuttering or crackling in your audio playback, try using a larger buffer size.
NOTE : This section does not apply to Mac OS X, and will not appear if you are running
that operating system. Mac OS X does not support ASIO (or WDM). Also NOTE that in
Mac OS 9, this section will simply be labeled “ASIO Buffer Size.” However, this does not
affect Sound Manager operation.
Bit Depth – This field will only appear in Mac OS 9 installations. The selections from this
drop-down list will be “16-bit,” “24-bit,” or “auto.” Some music programs in OS 9 will not
work properly with 24-bit audio, in which case the bit depth setting will either a) switch
automatically to 16-bit, or b) require that you manually change the bit depth setting in
your FireWire 1814
hardware page to 16-bit. Otherwise, leave the bit depth set to
“auto,” which is the default setting. It is also possible that slower CPUs may benefit from
a lower bit depth setting, so if your machine seems to be having a hard time handling the
audio processing (clicking, stuttering, etc.), try the 16-bit setting.
Sync Source – This field allows you to choose one of two internal clock sources
( digital inputs muted and digital inputs unmuted ) or one of two external clock
sources ( external - digital or word clock ). The Internal sync frequency can be set by
your audio software or operating system. This is the FireWire 1814’s default setting. Use
external digital sync when you wish to record from or lock to either the FireWire 1814’s
optical or coaxial ports, whether it’s set to adat or spdif operation. Use word clock to
lock to house sync, or a word clock source from a digital audio device.
Internal digital inputs – muted means that the FireWire 1814 is actively generating an
internal sync clock, and not listening to the digital inputs for sync source. This is the
default selection.
Internal digital inputs – unmuted means that the FireWire 1814 is generating a sync
clock, and also returning the sync clock through the digital inputs. Only use this mode
when your external device is clocking to the FireWire 1814.