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10. BALANCE ADJUSTMENT OF THE PICKUP’S
INPUT GAIN
The A6T has a dedicated input gain balance control located at
the backside of the preamp. The control is accessed through
a small hole with a screwdriver. This control is used to set the
basic balance of the UST and AST so the pickups can have
equal output signal strength. The control is set at the factory at
50 / 50 equal blend.
With the back, or bottom, of the A6T preamp up (so you are
looking at the bottom) turning the input gain control counter-
clockwise will blend more of the UST pickup into the mix. Turn-
ing the input gain control clockwise will blend more of the AST
into the mix.
After the installation of the system, the UST may have high out-
put. It may be high enough to cause the input gain stage of the
preamp to distort. After some time the output of the UST will
lower as it adjusts to the string / saddle pressure. After this time
period is good to check the balance of the pickups.
To check this, play the system through an amp system and listen
to sound of both sides of the mix control. most likely the UST
can have a little hotter output (louder) than the AST.
11. TROUBLE SHOOTING
11.1 No sound at all or intermittent sound
• Check the guitar cable and amplifier / mixer you are using.
• Check that the battery is not discharged. If the sound is
noisy or distorted, replace the battery.
• Check that the transducer and battery connectors are
inserted onto the pin headers of the preamp correctly.
• Check that the plug is making good connection with the
output jack. It may be so that the output jack is not sticking
out far enough when the strap button is on. To check,
unscrew the strap button off and plug in to the jack. If the
symptoms go away the output jack needs to be removed
and the nuts adjusted so the jack sticks out further.
11.2 Loud hum
• Check to see that the connectors of the UST / AST are
inserted with the two holes up. If these connectors are
upside down the system will work but it will buzz.
• Check that the connectors are inserted correctly onto
their pin headers at the preamp.
11.3 Resonance or distortion with some played notes.
After installation the UST pickup can have very high output,
enough to overdrive the B-Band preamp input, causing distor-
tion. The UST will lower in output, under pressure of the saddle,
in 1 to 3 days.
There are a couple places where a resonance can typically oc-
cur with some notes, causing distorted-sounding output. First,
check that the lead portion of the transducer to the preamp is
not touching anything and that the battery or output wires are
not loose and thus cause resonance.
With the UST, another place, which in some cases has caused
resonance, is the UST hole from the saddle slot to the inside of
the guitar. Using a soft padding in it has cured these problems
effectively.
With the AST, if resonance is occurring, it may be coming form
the first 5 mm (.20”) of the “lead” wire coming from the AST.
Using double stick tape, stick this first 5 mm (.20”) of the lead
to the guitar.
11.4 Imbalance, one or several strings sound louder or
quieter than the others (with UST)
If there’s only a very slight imbalance, let the saddle “shape” on
the UST for a few days. The fault may be repaired on its own.
Users have reported that after three (3) days the saddle has
settled on the UST and the balance becomes perfect.
11.5 Possible reasons for imbalance:
• The saddle or the bottom of the saddle slot is not flat.
• The saddle fits too loosely in its slot.
• The saddle slot might be too tight for the saddle to go in all
the way. Try pushing on the saddle firmly to seat the saddle
