Polycom Vortex EF2280, Справочное руководство

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I
NSTALLATION
V
ORTEX
EF2280 Reference Manual 16 Technical Support: 800.765.9266
Presets and
Multiple Vortex
Devices
P
RESET
0 is preconfigured for a system with multiple Vortex Devices. In this
preset, microphones are bussed out to other units on the W Bus. Microphones
are also input into each device on the W Bus (INPUT W
MO
in the Matrix).
If you have multiple devices in your system, save settings to a preset (Presets
16-47) on each device. Saving a preset will only save the preset on that par-
ticular unit. Also, remember to set the POWER ON PRESET to the User Preset
that you have saved your setting to otherwise the device will revert back to
Preset 0 (factory default) if power is lost.
C
HECK
S
URROUNDING
E
QUIPMENT
Now that the physical connections to the EF2280 are set up, it may be neces-
sary to check the surrounding equipment to make sure levels are set cor-
rectly. The following suggestions may be helpful in integrating the EF2280
into your system:
Pick a Standard
Signal Level
A standard nominal signal level should be used throughout the audio system.
Any equipment that does not operate at this standard level should be com-
pensated for as close to the piece of equipment as possible. A 0 dBu nominal
level is a good standard signal level. For example, a consumer VCR will gener-
ate a -8 dBu level. As soon as the VCR signal arrives at an input with some
gain control, the input gain should be adjusted so that you get a 0 dBu level,
i.e. adding 8 dB of gain.
Check Levels to
the Codec
Configure the matrix mixer output to the codec input.
The output gain of the matrix mixer should be set to match the nominal input
level of the codec. For example, if the codec accepts -10 dBV (-8 dBu) inputs,
8 dB of attenuation should be applied at the matrix mixer output to the codec.
Configure the matrix mixer input from the codec output.
The input gain of the matrix mixer should be set to match the nominal output
level of the codec. For example, if the codec outputs a -10 dBV (-8 dBu) level,
8 dB of gain should be applied on the Vortex matrix mixer input. This will
bring the codec level up to 0 dBu inside the Vortex matrix.
Configure Output
to Amplifier or
Loudspeakers
The loudspeaker level may be adjusted in several places: at the amplifier or at
the loudspeaker output of the matrix mixer in the EF2280. We suggest that
you adjust the loudspeaker level at the amplifier to preserve good gain struc-
ture. You should try to have a 0 dBu nominal level at the outputs by applying
input gain (See INPUTS tab on Conference Composer) to obtain a 0 dBu level
at the appropriate input.
Verify Room Gain
After adjusting the loudspeaker level, verify the room gain in your system
using the R
OOM
G
AIN
meter on the D
IAGNOSTICS
page of Conference Composer.
See Figure 8 below. The meter shows the room gain, which is the relative
level of the output level and the input level. While the EF2280 will operate in
positive room gain conditions, the room gain should be around 0 dB or a neg-