Polycom EF2201 Brochure & Specs page 46

Now that each Vortex has put its microphones on the W and X bus respectively, let's look how we can accomplish the voice lift
application on each Vortex. For this example, we will assume that two of the zone outputs are coming from each Vortex.
Vortex EF2280:00 Configuration
We specified in Figure 23 that in Zone 1 we want the Zone 2 microphones reinforced at a level of -9dB, the Zone 3 microphones
reinforced at a level of –6dB and the Zone 4 microphones reinforced at a level of -3dB. InstantDesigner defined the first four
microphones on EF2280:00 as being in Zone 1, the next four microphones as being in Zone 3 and the first four microphones on
EF2280:01 as being in Zone 2, and the remaining 4 microphones as being in Zone 4. To create the appropriate sound voice lift
attenuations, we can either apply attenuations on the incoming signal in the sub-matrix, or we can set the sub-matrix cross point
gain to 0dB and apply the appropriate attenuation in the main matrix. For this example, we will apply the attenuation in the sub-
matrix to help illustrate how to use the sub-matrix. In a larger system with more than two Vortexes, we would have to use the sub-
matrix to get the appropriate signals and levels. As shown in Figure 28, the microphones from Zone 2 (on EF2280:01) are available
on Vortex EF2280:00 as input WB1 and the microphones from Zone 4 are available on EF2280:00 on the input signal XB1 (the "1"
on the bus signal XB1 name indicates the signal is sent from Vortex EF2280:01 which has device ID 1).
Based on the sound reinforcement zone definitions in Figure 23, we will attenuate the Zone 2 microphones going to Zone 1 by 6dB
before sending to the Zone 1 output on EF2280:00 and attenuate the Zone 4 microphones by 3dB before sending to the Zone 1
output on EF2280:00. This attenuation is performed by setting the cross point gain of WB1 and WM1 to –6dB, and by setting the
cross point gain of XB1 and XM1 to –3dB. In the main matrix for Vortex EF2280:00, the WM1 and XM1 signals will be summed
together to form the local Zone 1 output as shown in Figure 23.
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