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Clocking
The Pro64 network offers the most flexible clocking and synchronization
options in the industry. Pro64 devices support three ranges of variable
sample rates, from 44.1/48kHz± to 192kHz±. Because no sample rate
converters are used, audio transmission is kept fast and clean, eliminating
the audio artifacts and signal degradation inherent to sample rate
conversion—even when syncing to an external clock source.
Any Pro64 I/O module can be designated the Clock Master for the
network, generating and distributing its internal clock. Digital I/O
modules are capable of syncing to and distributing an external clock
from a Word Clock or AES3 source.
Control Data
The Pro64 Series has built-in, dedicated bandwidth for 14 channels of
non-audio control data through the use of Aviom’s innovative Virtual
Data Cables™. These data streams are always available to carry MIDI,
RS-232, RS-422, or GPIO (General Purpose I/O), and they never compete
with the audio channels for network resources, regardless of the system
configuration. (Not all VDC™ data types are supported on every Pro64
module.)
Because VDC inputs are simply incorporated into the A-Net stream,
these control signals can be transmitted over very long cable runs
and even across an entire Pro64 network, significantly expanding the
applications possible with MIDI, RS-232/422, and GPIO. And as with
audio signals, VDC control data can be input anywhere and output
anywhere else in the network.
A-Net Ports
Pro64 I/O modules have dual A-Net ports, labeled A and B. Both ports
carry a bidirectional A-Net stream at all times. (That is, both ports are
always transmitting and receiving A-Net data.) Pro64 networks can be
configured in one of two operational modes, Auto Mode or Manual
Mode, depending on the requirements of a particular system.
In Auto Mode, there are no connection rules; connect a Cat-5e cable to
either the A or B port and the system does the rest. Auto Mode provides
a true audio network with 64 available “Slots” for transporting audio (at
44.1/48kHz). Every audio Slot is available everywhere in the system, with
no upstream/downstream restrictions.
In Manual Mode, the Pro64 network becomes a 64x64 system (at 48kHz),
similar to a traditional stage-to-FOH snake. At every point in the Manual