8
on and off. Optionally, this jack may be employed to feed the EFX signal to an
external effects unit the output of which could be returned via an input channel -
perhaps channel 9/10 or 11/12 (15/16,17/18) if the effects unit is stereo. In this
mode, the channel fader would become the master effects return control, therefore
be sure to set that fader fairly low and adjust to desired levels. Be sure to turn the
EFX send control off in order to avoid creating a loop. Also, be sure to pull the EFX
MASTER fader down to the off position.
Phones Jack, Level Control & Sources
The PHONES jack accepts standard stereo headphones and is located in the upper
right area of the panel. The PHONES level control is located in the lower right area.
The source for all headphone signals is the MONitor bus until a CUE button is
depressed at which time only the cued channel can be heard through the phones.
Level Meters
These meters follow either the Left and
Right MAIN bus activities or a mono mix of
the mains on the Left-meter and monitors
on the Right-meter, all depending on the
position of the EQ/AMP ASSIGN button. If
either or both CLIP lights at the top of the
level meters is flashing too much of the
time, lower the appropriate MAIN MASTER
level to avoid possible distortion on peaks.
Amp 1 & 2 Inputs
These are switching jacks which enable
you to directly access either or both chan-
nels of the built-in power amplifier while
disconnecting them from normal internal
functions. This permits you to insert an
external-EQ, a processor /crossover (e.g.
élite) or a compressor/limiter between the
mixer section’s POST EQ LINE OUTPUTS
and the AMP 1 & AMP 2 INPUTS thus pro-
viding the 100% signal processing essential
for these functions to work properly.
User tip: If you have an electronic-cross-
over or processor/crossover, you can drive
subwoofers and full-range cabinets in a
biamped system with the AP812/818. The hookup goes as follows:
1. With the EQ/AMP ASSIGN button down in the MAIN/MON position, run a patch
cable from the POST EQ MAIN (L) LINE OUTPUT to the input on an electronic
crossover/processor.
2. Now run a second patch cable from the low-frequency or subwoofer output on
the crossover to the AP812/818’s AMP 1 INPUT and a third patch cable from the
crossover’s high-frequency or full-range output to the AP812/818’s AMP 2 INPUT.
3. Now connect two 8 ohm subwoofers or one 4 ohm subwoofer to the AMP
1 SPEAKER connector/s and two 8 ohm full-range cabinets to the AMP2
SPEAKER connector/s.
4. The complete system is now functional, not including monitors. How-ever, if you
need to vary the comparative volume levels of the subwoofer/s relative to the full-
range cabinets, another setup will be required with an external power amp for
the subwoofers or employing powered subwoofers. In that system, AMP 1 would
be for full-range speakers and AMP 2 would be for monitors. In other words, this
is a standard setup but with the MAIN (L) LINE OUTPUT going to the input of
the processor/crossover and then to an external amp driving the subwoofer/s, or
simply direct to the input of a powered subwoofer (ours have crossovers built in).