TANDBERG 550MXP - Manual (Page 157)

Administrator Settings
147
4.5.1 Inputs
Mic 1 and Audio input 2
By default, both inputs are enabled. Just plug in an audio source and it is active. Audio inputs that
are On will automatically be mixed. Unconnected inputs will automatically be muted. Select Off to
prevent audio/noise from connected but unused inputs. The activated audio sources are stored
on camera presets.
Mic 1 is intended for electret type microphones. The microphone inputs are balanced with 24V
phantom power.
The Audio input 2 is intended for connecting external playback devices when set to On, but the
input can also be configured as a microphone input by selecting Mic. When set as a microphone
input there will be an echo canceller working on both inputs to prevent unwanted echo to be
heard at the far end. When connecting an external playback device to this input there will be no
echo cancelling and the audio source connected to Audio input 2 will be heard from the local
loudspeaker as well.
Level Settings
It is possible to adjust the audio input levels according to which external audio equipment is
connected. The on-screen audio level indicator will make it easier to set the correct input level
settings. The input level should be adjusted so that the average level reaches the preferred level
marker. The audio inputs are adjustable in steps of 1.5 dB from 0 dB to 22.5 dB.
The default level for Mic 1 is set for use with an Audio Technica AT871R or AT841R microphone
in an average videoconferencing room. The gain can be adjusted correctly for a wide range of
microphones.
A few examples of microphone levels are:
Audio Technica
AT871R
+3dB (default)
Audio Technica
AT851R +7dB
TANDBERG Audio
Science +19.5dB
Audio input 2 is set to a default level which is adhered to by most manufacturers of audio-visual
equipment and is a level at which most audio-visual equipment (CD-players, VCRs or DVDs) will
work.
Please see
Interfaces for details on the audio connectors.