Rear Panel Description - AKG AS8 Operating Instructions Manual

R P D
EAR ANEL ESCRIPTION
MIC/LINE INPUTS 1-8 - Accepts balanced or unbalanced signal. Fully balanced differential input, RF filtered.
DIR OUT - Provides a line level signal from each individual channel. The direct output is a post-VCA signal. Any attenuation
from the auto mixing process, compressor/leveler system or remote attenuation will be reflected in the direct out signal.
This provides versatility for different mixing applications such as distributed overhead speaker systems. This 100 Ohm
output provides a +20dBu max signal into a high impedance load.
Note: The DIR OUT shares a ground with the MAIN OUT.
--Don't use the CHANNEL IN grounds for the DIR OUT!--
When connecting to other equipment, the ground connection of the MAIN OUT will
also be adequate for all the direct outputs. A separate ground connection is not
needed for each direct out.
FUNCTION SELECTION SWITCHES 1-8 - Allow various functions of the input channels to be set.
Dip switch 1 chooses the channel mode. Auto mode (down position) sets operation to automatic, with channel gain
determined by its signal level relative to other microphones. When a channel is set to Direct, its signal will affect the levels
of other channels set to Auto, but it will not be affected by other channels (no NOM attenuation will occur on a channel
set to Direct). Note, however, that the Remote Level control feature functions regardless of the setting of the Auto/Direct
mode switch.
Dip switch 2 turns +15V phantom power on (down position) or off (up position).
Dip switches 3 and 4 set the gain of the input preamplifier. 0dB gain, for line level sources, is set when switches 3 and 4
are in the up position. 30dB gain, typically for high output (electret) microphones, is set when switch 3 is in the up position
and switch 4 is in the down position. 50dB gain, used for low output (dynamic) microphones, is set when both switches
are in the down position.
MAIN OUT - Provides a balanced system output. The Main Out may also be used in an unbalanced mode by connecting
the "+" terminal of the Main Out to the signal lead of the unbalanced device, and the ground terminal of the Main Out to
the ground of the unbalanced device. Do not connect the "-" terminal of the Main Out.
REMOTE LEVEL CONTROL - Allows remote control of both channel levels and the master level. Either 10K ohm linear
pots or an adjustable DC control voltage may be used. The volume control action is internally audio scaled in software. This
gives an "audio-taper" characteristic to a linear pot. Approximately 15dB of attenuation happens for the first half of pot
rotation, with the rest of the attenuation (to full off) happening in the second half of pot rotation. When using a DC control
voltage, the control constant is .167V/dB (or 6dB/V) from 0V to 5V. At 5V, the channel is turned completely off. The control
voltage should not exceed 5V. Below is a listing of the 15 pins on the Remote Level control port and their functions.
AS8 REAR PANEL
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