ATOMIC AMPS REACTOR 50/50 MANUAL
7
Your Atomic Reactor 50/50 is vacuum tube driven, and therefore requires
maintenance. Power tubes have a life expectancy of approximately 1000
hours. Regular play requires regular service.
Tube Replacement
: The 50/50 utilizes 2 × 12AX7 tubes and four high
quality JJ brand 6L6GC tubes, selected because they offer excellent sound
quality. You will notice degradation when tubes need to be replaced. The
power section is built to work with any properly biased 6L6 or EL34 tube.
When tubes need to be replaced, use a qualified amplifier technician.
Output Tube Bias Adjustment:
A technician will bias your amp when new
tubes are installed. However, you may find bias drifts over time. You can
check and adjust
this yourself.
Each channel of the Reactor 50/50 is
equipped with a front panel bias test point and adjustment point. A
common ground serves both channels. The bias trim sets the idle current in
the output tubes, properly matching the amp’s performance characteristics
to the type of tubes used. Each tube type and brand may require a slightly
different bias, and settings should be checked when tubes are replaced. A
properly biased amp will sound great and will run reliably and safely. An
amp’s bias can drift with extended use. To bias the Reactor 50/50, turn
main power ON and take the desired channel out of STANDBY. Touch the
negative lead (black) of a VU Meter to the common ground on the front
panel of the Reactor 50/50. Touch the positive lead to the test point for the
channel you plan to adjust. Adjust the trim with a small flathead
screwdriver until the meter reads in the range of 70–90ma. Once the first
channel has been properly biased, put it in standby and repeat the bias
adjustment process for the second channel.
Front panel bias controls of the Reactor 50/50.
