Virtual Channel Summary - Polycom SoundStructure C16 Design Manual

installation "Podium mic" were wired to input 1 and on another installation "Podium mic" was wired to input
17. The same control system code can be used on both installations because the SoundStructure devices
translate the virtual channel reference to the underlying physical channel(s) that were specified when the
virtual channel was defined. By using the same API commands on different systems that refers to "Podium
mic", the control system code is insulated from the actual physical connections which are likely to change
from one installation to the next. The virtual channel definition makes the design portable and easily
reusable.
The use of virtual channels also improves the quality of the control system code because it is easier to write
the correct code the first time as it is more difficult to confuse "Podium mic" vs. "VCR audio" in the code than
it would be to confuse input 7 on device 2 vs. input 9 on device 1. The clarity and transparency of the virtual
channel names reduces the amount of debugging and subsequently the amount of time to provide a fully
functional solution.
Another benefit of working with virtual channels is that stereo signals can be more easily used and
configured in the system without having to manually configure both the left and right channels
independently. As shown later in the guide, the SoundStructure Studio software automatically creates the
appropriate monaural mixes when interfacing a stereo signal to mono destination and vice versa.
Using virtual channels that represent stereo physical signals reduces the chance of improper signal routings
and processing selections. The net result is that both designs and installations can happen faster and with
higher quality.The motivation for using virtual channels is to make the system reusable across different
installations regardless of how the system is wired because the SoundStructure device knows how to
translate commands that are sent to virtual channels, such as "Podium mic", to the appropriate underlying
physical channel.
Note: Defining Virtual Channels
Virtual channels are a high-level representation that encompasses information
about the physical channel. Virtual channels are used to configure and control the
underlying physical channel(s) without having to know the underlying physical
channel numbers.

Virtual Channel Summary

Virtual channels are a new concept introduced for SoundStructure products that makes it possible to refer
to one or more physical channels at a higher level by creating a virtual channel and a memorable virtual
channel name.
Using SoundStructure virtual channels is the only way to configure and control the underlying physical
channels with third-party control systems. The physical input and output channel numbering described in
the section Understanding Physical Channels
virtual channel knows which physical channel(s) it refers to.
By using virtual channel names rather than hard wiring physical input and output channels in the control
system code, the control system source code is more portable across other installations that use the same
virtual channel names regardless of which physical channels were used to define the virtual channels (in
other words, how the system is wired).
Virtual channels also simplify the setup and configuration of a system because it is easier to understand and
view changes to Podium mic than it is to have to refer to a signal by a particular physical input or output
number such as input 17.
Polycom, Inc.
is used only in the definition of virtual channels so that the
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