Listen AudioConnect Series, Руководство пользователя

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Operation
AudioConnect
TM
Manual
9
Front Panel
Status LED

Off: No power has been applied to the
unit

Yellow: Power has been applied to the
unit, but there is no USB
communication with the computer

Green: Power has been applied to the
unit and there is USB communication
with the computer
Mic In

Microdot (10-32 female RF) connector

A constant voltage bias can be supplied for Listen, Inc. SCM Microphones as well as other
compatible electret-based measurement microphones.

Open Circuit Bias Voltage: 10 VDC

Bias voltage can be enabled for both inputs from the Message Step. See
SoundCheck Control
on page 7
.

Disable the Bias voltage when running the Sound Card calibration process on the microphone
inputs or when running Self Test.
LED Level Indicators

Off: Output level is less than -50 dBFS

Green: Output level is between -50 dBFS and -3 dBFS

Yellow: Output level is between -3 dBFS and 0 dBFS

Red: Output level has reached 0 dBFS
+20 dB Gain

Off: No gain applied. 0 dB

Green: +20 dB gain is applied

Applies to Mic In and Line In. Does not apply to Digital In.

Independently switchable on each channel
Headphone Out

Standard 1/4” TRS stereo headphone connection

See
SoundCheck Control on page 7
Note:
Prior to serial number 40501270109, firmware 1.61, the headphone output polarity is inverted
for both channels. Polarity tests using the headphone out will need to be adjusted accordingly.
Polarity Limits may need to be changed from a Lower Limit of 0 to an Upper Limit of 0.
Figure 4-4: Front Panel