Operating Instructions - AKG AS8 Operating Instructions Manual

O I
PERATING NSTRUCTIONS
Setup of the AS8 consists of choosing rear panel dip switch options, setting front panel levels, and adjusting the
compressor/leveller (if used). Using the Remote Level Control capability of the AS8 is addressed in the next section. When
the power is turned on to the AS8, it will display its LecNet address on the Channel On LEDs for 1.5 seconds before entering
normal operation. Channel 8 On LED represents the most significant bit of the binary address, while Channel 1 On LED
represents the least significant bit.
1) Select Auto or Direct mode using dip switch 1 on channels 1-8. Normally, all speech microphones would be in the Auto
mode. Microphones used for music (e.g. choir mics in a church sound system), or inputs attached to line level devices
like tape players or VCRs are best used in the Direct mode. The Remote Level Control terminals may be used to
manually turn off Direct mode microphones when they are not in use.
2) Turn Phantom power on or off as needed, using dip switch 2 on channels 1-8. Dynamic microphones need no phantom
power, but electret types will need phantom power to operate properly.
3) Set up the preamplifier gain using dip switches 3 and 4 on channels 1-8. The 0dB position is used for line level sources
like tape players or VCRs. The 30dB position works well for higher output microphones like electrets. The 50dB position
is best for dynamic microphones, or electret types where the distance from the talker to the microphone is more than
3 feet or so.
4) Set the Main Level control between 5 and 6. While speaking into each microphone in turn, adjust the Channel Level
to give adequate volume level. The normal operating position of the Channel Level control should be between 10
o'clock and 2 o'clock. Try to adjust all microphones to about the same volume level, as this will result in the most
optimum automatic action.
5) If the compressor/leveller system is to be used, switch the In/Out front panel switch to the In position. With a normal
talker, adjust the Threshold pot until the 3dB Gain Reduction LED flickers on. The system volume level may need to
be readjusted at this point using the Main Level control. Next, check that a loud talker turns on most or all of the
remaining Gain Reduction LEDs. Finally, with a soft talker such that no Gain Reduction LEDs are lit, be sure there is
no feedback or ringing in the system.
The system is now ready for use.
Note: Be sure to set the AS8 back to "Local" mode after using the software-based control panel on a PC. If the unit was
left in "Remote" mode and there is no PC available, it will be necessary to perform a "Reset to Local" procedure.
1. Turn off the power to the AS8.
2. Short Pin 10 to pin 15 on the rear panel DB15 connector while turning on the power switch.
3. Remove the short from pins 10 and 15.
All subsystems are now in "Local" mode and controllable from the AS8 front/rear panel.
There are three subsystems that can be effectively disabled if they are left in "Remote" mode:
1. The Compressor/Leveller subsystem. If this function is in "Remote", the symptoms will be no response from the
Threshold control and the In/Out switch.
2. The Auto/Direct function. If this function is in "Remote," the AS8 will ignore the state of the rear panel dipswitches.
3. The Remote Level Control subsystem. If this function is in "Remote", there will be no response from the remote level
control.
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