User`s manual

Bias Test Jacks:
Three standard tip jacks are available to allow easy bias current measurements without
removing the chassis. Refer to the section on biasing for instructions on the use of these
jacks.
Bias control:
A locking mil-style RV6 trimpot is provided to allow adjustment of bias current. The outer
locknut must be loosened before adjusting the screwdriver-slot control. Refer to the
section on biasing for further instructions.
Effects Loops:
This is a 1/4" TRS (tip/ring/sleeve) insert style jack. There is a separate loop for each
channel, and they function completely independently. The nominal 0dBu level allows use
of line-level (pro) effects for lowest noise levels. The TRS insert jack allows use of a
single TRS cable to connect the effects, instead of the two 1/4" cables normally required
for an effects loop. The TRS cable (also called an “insert” cable) is a cable that has a
stereo ¼” jack on one end and breaks out into two mono ¼” jacks that go into the input
and output of the effects unit. These insert cables are available at most music stores
(they are typically used to connect compressors or other effects to a single channel on a
mixing board). Alternately, you can make or buy a stereo to two-mono “pigtail” adapter
cable (available from places like Radio Shack) and use standard ¼” cables to connect
the effects.
Once properly connected, adjust the effects unit’s input level control so the signal
presence LED is lit (if there is one) and the clip LED occasionally lights on peaks or
doesn’t light at all, depending on the effect’s requirements. Then adjust the effects unit’s
output level so the Sabre’s volume is the same with the insert cable plugged into the back
of the amp or unplugged. Refer to the effects unit user manual for proper adjustment in
case it differs from these instructions.
Although there are two independent effects loops, it is not necessary to use two separate
effects units with the Sabre. Most rack mount effects are stereo, and have independent
channels when both are used. To use a single stereo effects unit with the Sabre, simply
connect two TRS cables, one from each effects loop jack, to the inputs/outputs of the
stereo effects unit. Of course, the same effects patch will be active for both channels, so
you will have to change channels and effects patches at the same time to have different
effects on each channel. There are midi footcontrollers on the market that will allow
control of amplifier channel switching and effects patch changes at the same time.
There is, however, a more elegant solution to using a single effects unit: the TC
Electronics G-Major multi-effects processor. This is the recommended effects unit for
use with the Sabre. It has a unique relay output jack feature that is perfectly suited for
use with the Sabre’s footswitchable functions. This is a stereo output jack that has two
indepent patch-controllable relays connected to a single stereo jack on the rear of the
unit. By simply connecting a stereo cable from the relay output jack on the G-Major to
the stereo footswitch jack on the rear panel of the Sabre, and connecting two TRS cables
from the effects loop jacks of the Sabre to the inputs/outputs of the G-Major, you can
program and control G-Major effects patches, Sabre channel selection, and Sabre boost
switch functions all at the same time with a single patch change on the G-Major (or single
step on the G-Major’s footcontroller).