Aphex 1788A Premium Eight Chan Mic Pre - Manual (Page 8)

Page 8
MICROPHONE PREAMPLIFIER
Page 9
Instruction Manual
2. QUICK START
2.3 GETTING UP & RUNNING
Here’s a step by step instruction on using the 1788A. Please plug a
microphone into Channel 1 and connect the CH1 Main Output to a
mixer or recorder input. Turn all units on.
1. Press the LOCAL CONTROL button in the Control Block to enable
the front panel controls. It’s a good idea to get into the habit of
tapping the LOCAL CONTROL button every time you need to make new
adjustments at the front panel just to make sure you have access.
2. Press the CHANNEL SELECT button on the front panel labeled “1”.
This attaches the preamp controls to channel 1.
3.. If the microphone you are using requires phantom power, press the
Phantom +48V button. You should see the +48V light come on in
the first channel’s Channel Status Readout. If you are using a dynamic
or ribbon microphone, leave the +48V off or turn it off if it is on.
CAUTION 1: Beware of the potential shock hazard with
phantom power. Don’t touch the contacts.
CAUTION 2: It has been reported that some ribbon mics may be
damaged by phantom power. This is unusual, but it’s a good idea to
keep it turned off when not required.
4. At this point you can try all the other parameters like PAD, POL, etc.
by pressing their buttons to get the feel. You should be able to adjust
the preamp gain, and hear the mic through your system. Next, we
need to set the maximum output level to match your mixer or recorder.
Turn all the preamp functions off. Turn down your speaker volume.
5. Turn on the 0dB test tone by holding down the 0dB 700Hz TEST
button and tapping the channel 1 select button. The Ch 1 bargraph
meter should go to full scale indicating tone presence. You should hear
the tone and see it’s presence on your equipment.
6. Select Main Out with the GAIN SELECT button and adjust the
output level with the ADJUST control. If you know the rated maximum
input level (MIL) to your recorder or mixer, set the 1788A’s output to
that value. For example, if your recorder can take +24dBu max input,
set the 1788A’s output to 24 as indicated on the 1788A’s digital gain
readout. That makes sure the dynamic range of the 1788A is matched