User`s guide

PC setup
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Record Buffer setting
This setting is used to maximize performance of the system when recording high track counts over long (two
or more hours) periods of time. The default setting is 11520. The Record Buffer setting can be decreased in
order to ensure lower latency, however gaps and noise during recording may occur.
Playback / Monitor Device
This control panel allows you to configure your monitoring device. Only supported devices will display in the
drop-down menu.
Panel
This button is used to open the ASIO panel for the supported monitoring device.
About
This button opens the About dialog, which contains version and copyright information.
Notes on word clock, synchronization and latency
What is word clock?
Word clock is a signal used to synchronize digital audio devices, such as digital mixers, digital audio
converters and digital audio workstations. Word clock is used to maintain a constant and accurate timing
reference to avoid data errors. Word clock is essential to avoid frequency drift between the internal clocks of
each device in the digital audio signal path. For the purposes of this setup, word clock sync can be derived
from the Optical S/PDIF, BNC word clock and AES/EBU connections.
Why is synchronization important?
If word clock is not distributed properly a number of audible problems can occur including a collapse of the
stereo image and loss of detail in high and low frequencies. Whenever possible, you should have a dedicated
word clock connection between all digital audio components. The device which maintains the word clock on a
network is the master clock.
What is latency?
Latency is the delay caused by the time it takes a computer to process data. All computer based recording
systems have some measurable (but not necessarily audible) latency.
For this recording system, latency is determined by the following formula:
REAC Input Latency = Record Buffer size / Sample Rate
REAC Output Monitor Latency = REAC driver pre-roll * REAC Input Latency + Output Monitor Hardware Latency
Note: The Output Monitor Hardware Latency value varies with each system. In the example below, a
value of 6 milliseconds is used.