7. CONNECTING THE PICKUPS AND WIRING
TO THE PREAMP
7.1
Open the preamp and see the picture for connections.
Connect the pickup(s), AG-MIC, and battery cable harness.
Notice that the small holes on each connector of the transducer
and battery cable harness should point upwards.
If the UST or AST are connected improperly, a loud audible hum
will occur. Make sure that they are connected correctly.
7.2
Inside the A2 there are four DIP-switches:
Switch #1 is an on-off switch for the treble boost on #1 chan-
nel (normally UST). Set that at on-position if you prefer a mild
treble boost.
Switch #2 is an on-off switch for the #2 channel bass roll-off 6
dB (-3 dB @ 500 Hz when at on-position). Set it at the on-po-
sition only when using a condenser microphone to reduce low
frequency feedback.
Switch #3 is an on-off switch for second channel bias-voltage
(9-volt phantom power). Set it at on-position only when you use
condenser microphone on the #2 channel.
Switch #4 is an on-off switch for channel two gain reduction (27
dB at off, and 0 dB at on). This also must be set it at on-position
when you use a condenser microphone or passive magnetic
pickup connected to the #2 channel.
From the factory, all the switches are set at off-position.
Another option is that a magnetic pickup can be connected to
channel #2 by soldering the pickup's wiring directly to the in-
put pin headers. Check the polarity before installing. Use a low
temperature soldering gun. Be careful to do this install and try
not to heat up the pin headers. If too much heat, it is possible to
melt the plastic or damage the circuit board. We recommend a
professional luthier or guitar tech to do installation.
7.3
. Close preamplifier enclosure
8. INSTALLING THE PREAMP
For the next portion of the installation, be careful not to catch
the pickups on anything as you work; inadvertent tugging may
cause damage to the pickups or pull the connectors off the pin
headers at the preamp.
For AST please note to lift one corner of the protective layer of
the mounting adhesive so it is easier to remove later.
8.1
Unscrew the strap attachment, the small nut and the small
dress washer from the endpin jack. Make sure that the large
nut; lock washer and large dress washer are threaded onto the
jack almost all the way to the opposite end of the output of
the jack.
8.2
Next, test-fit the jack in your strap button-hole. Adjust the
large nut so that only the smaller threaded section comes al-
most entirely out of the guitar. Put the dress washer and the
small nut onto the threads outside the guitar. Tighten securely
using an appropriate wrench. Prevent the jack from rotating du-
ring tightening by inserting a small Allen wrench into the holes
A2
UST or AST
(Channel #)
AST, MIC or MAG PICKUP
(Channel #2)
Battery wire
#
#2
#3
#
+
-
NOTE! PIN HEADER POLARITY
(IF INSTALLING MAGNETIC PICKUP)
