Atomic Reactor FR User manual

Atomic Reactor FR
THE WORLD’S FIRST AND ONLY TUBE-POWERED
FULL RANGE GUITAR AMP/PERSONAL MONITOR
www.atomicamps.com
OWNER’S MANUAL

Atomic Amplifiers and Atomic Reactor FR are trademarks of Atomic Amplifiers LLC.
Any other product names, trademarks or names are the property of their respective owners
which are in no way associated with or affiliated with Atomic Amplifiers LLC
© 2009 Atomic Amplifiers LLC. All rights reserved.
Atomic Amplifiers LLC • 476 Grace Trail, Orange, CT 06477
[phone] [tel] • i[email protected] • www.atomicamps.com
WARNING!
TO PREVENT FIRE OR SHOCK HAZARD,
DO NOT EXPOSE THIS UNIT TO RAIN OR
MOISTURE.
NO USER SERVICABLE PARTS INSIDE,
REFER SERVICING TO QUALIFIED
PERSONNEL ONLY.
SERVICE BY PERSONS OTHER THAN
ATOMIC AUTHORIZED SERVICE
TECHNICIANS MAY VOID WARRANTY.
THIS UNIT MUST BE
EARTH GROUNDED.

1
REACTOR FR USER MANUAL
TABLE OF CONTENTS
2 The Atomic Reactor
3 Summary of Components
4 Controls & Connections
6 Using the Reactor FR
7 Rig Diagrams
8Maintenance
9 Service
10 Trouble
11 Specs
12 Warranty

2
THE ATOMIC REACTOR FR
Your new Atomic Reactor FR is the world’s first and only tube-powered
full-range guitar amp and personal monitor. The Reactor FR is a musical
instrument in its own right—designed and built with the performing or
studio guitarist in mind, but also extremely effective for acoustic guitars,
vocals, keyboards and other electronic instruments, or any application
where a full range powered speaker system is needed.
The Atomic Reactor FR is the result of our design team’s tireless efforts
to create a superior sounding amplifier for the modern digital guitar rig. A
timeless, all-analog showpiece, the FR ensures that preamps, modelers
and simulators will sound their very best, by imparting to these products
the genuine warmth and feel of a real tube amp. Even as digital guitar
technology advances, the Reactor FR will remain a viable and valuable
investment in tone.
The Cabinet and construction of the Reactor FR are engineered to
withstand the demanding conditions of professional musical performance
and still operate flawlessly night after night, whether on stage, in the
studio, or in a standalone setting.

3
SUMMARY OF COMPONENTS
The Reactor FR is made up of two independent systems: a 50 watt RMS
tube audio power amplifier, and a very high efficiency tuned speaker
system.
The power amplifier employs one 12AX7 and two “JJ” Brand 6L6GC
vacuum tubes to deliver full-rated power over a full frequency response,
with high headroom and very low distortion. In other words, this is an
amp “without an opinion”. It will amplify but not color or alter the tone of
the input signal. When the sound source is a digitally created model or
simulation, however, the Reactor FR is able to restore the musical
characteristics and feel that we usually expect only from a well-designed
analog tube amp.
The speaker system consists of a 12” speaker, a 4” tweeter, and a
crossover network. It is correspondingly wide range and smooth, without
sharp peaks or ragged response. The high efficiency of the cabinet
design, coupled with the dynamic abilities of the amp and speaker,
provides a level of performance that one would expect only from an much
more powerful system.
Through the use of the speaker jack and switch, the amp may be used to
drive an external speaker, or the internal speaker may be used with an
external amplifier. See Controls & Connections (p. 4-5) for more
information.

4
CONTROLS & CONNECTIONS
Figure 1: Controls & Connections
eUnbalanced (¼") Input – Unbalanced input of the amplifier. The ¼”
input overrides the balanced XLR input if both are connected.
rBalanced (XLR) Input – This female XLR-type connector accepts a
balanced or unbalanced line level signal.
tBalanced ( XLR) Thru – This male XLR connector produces exactly
the same signal that is connected to the balanced XLR input jack,
whether or not the Reactor FR is switched ON. Note that the THRU only
passes the XLR input and NOT the ¼" input signal.
uPower Switch – Control to switch the amplifier ON or OFF.

5
iStandby Switch - The standby switch is used to turn off the high
voltage to the amplifier's tubes, preventing damage while the amp is
warming up. Please allow 30-60 seconds after switching the Reactor FR
on before bringing it out of standby for normal use.
oGround lift – When there’s a hum or buzz in your system, the ground
lift can often eliminate it. The ground lift works on all inputs.
pMaster Level Control - Adjusts the amplifier’s overall volume.
aTweeter Level – Adjusts the volume of the high frequency component
of the amplifier’s sound.
TONE TIP: The high-frequency response is “flat” with the Tweeter Level
at 12 o’clock. The “sweet spot” will vary depending on your listening
environment, ears, and the position/placement of the reactor RR. Turn
the control downwards for a warmer darker tone or increase for added
brightness and sparkle.
sSpeaker Switch – Sets the function of the Speaker Jackdas follows:
Switch Setting Internal Speaker Jack Function
ON: ON ON
OFF: OFF*ON
EXT. AMP: In this position, the jack is converted from an output
to an Input for the internal speaker, effectively
converting the Reactor FR into a passive cabinet for
use with an external amplifier.*†
*WARNING: Do not operate the internal amp with no speaker or load connected!
† NEVER connect an external amplifier to the speaker jack when the speaker
switch is not set to Ext. Amp as doing so could damage both amps.
fCooling Fan - This very quiet fan operates at a constant speed
whenever the Reactor FR is powered on.
gPower Input - This is where you connect the supplied AC line cord to
provide power to the Reactor FR. The power inlet also houses the Fuse
Compartment which must be opened to replace the fuse. In order to
convert the Reactor FR from 115v (US) to 230v (EU) operation (or vice
versa) remove, rotate, and replace the fuse compartment.

6
USING THE REACTOR FR
The Reactor FR is easy to use and offers a range of controls to fit a great
range of musical performance requirements. NOTE: Before connecting the
Reactor FR, it is advised that you should lower the output level of your
preamp, processor, or other source device.
1. Connect the AC Cable supplied with your Reactor FR to the unit’s
AC Power Input located on the back panel of the Reactor.
2. Using a high-quality cable, connect a signal source to either the
Unbalanced (¼”) Input or the Balanced (XLR) Input.
3. Turn the Power Switch to ON (it should light up).
4. IMPORTANT: Wait at least 30-60 seconds for the amplifier to
warm up, then set the Standby Switch to ON. The Reactor FR is
now ready to be played.
5. Increase the level of your instrument or processor and set the
Master Level of the Reactor FR to an appropriate level. Adjust
the tweeter level to taste.
REMINDER: The Balanced XLR Thru is an output, designed to pass the
Balanced signal from the XLR input through to a second amplifier, mixer,
recording console or other device. It is not wired to the unbalanced ¼“ in.
WHO’S DRIVING? Whether you like to run your source signal “Hot” and
lower the master volume of the Reactor FR, or crank the Reactor and use
the upstream to set listening level is up to you. Either way, you will find
that the Reactor FR operates quietly and produces a pleasing, high
quality listening experience.
POSITION & PLACEMENT As with any audio system the floor, walls, and
other characteristics of your performance space will shape the sound of
the Reactor FR. You can increase openness and clarity by elevating the
Reactor FR from several inches to several feet above the floor using
casters, blocks, or an amp stand.

7
RIG DIAGRAMS
MONO GUITAR RIG - Guitar rack
(ex: Fractal Axe-FX Ultra) connected
to the balanced XLR input or the ¼”
unbalanced input of the Reactor FR
(whichever is convenient for you).
STEREO GUITAR RIG – Connect the left and right outputs of a stereo
processor to the inputs of two Reactor FRs to create a wide, 3D sound.
DUAL MONO
Connected as in the mono setup above, but with the THRU of the first
Reactor FR connected to the input of a second Reactor FR (XLR only.)

8
MAINTENANCE
Like every legendary guitar amp, the Reactor FR is vacuum tube driven,
and therefore requires tube maintenance. The power tubes have a life
expectancy of approximately 1000 hours. Tube amps that get regular
play should be regularly serviced.
Tube Replacement: The Reactor FR utilizes one 12AX7 tube and two
high quality JJ brand 6L6CG tubes specifically selected because they are
capable of producing the best possible sound quality. Depending on your
level of use, you will notice a deterioration of sound quality when tubes
need to be replaced. For continued optimum performance from your
Reactor FR, tubes should only be replaced with tubes of the same type.
The power section is built to work with any properly biased 6L6 or EL34
tube.
Output Tube Bias: Your new Reactor FR has an internally mounted
variable bias control. The bias control is used to set the idle current in the
output tubes, properly matching the amp’s performance characteristics to
the type of tubes used. Each different tube type and brand may require a
slightly different bias setting. An amp’s bias can also drift over time as
the tubes’ bias requirements may change with extended use. The bias
should be checked periodically and when the tubes are replaced. A
properly biased amp will sound great and will run reliably and safely.
WARNING! The internal voltages of tube type amplifiers are
lethal and capacitors are capable of storing these lethal
charges. To ensure tone and safety, biasing the amp should be carried
out by qualified personnel only.
The Fuse: The fuse protects the amplifier in the event of an electrical
fault or tube failure. If a fuse blows, replace it only with one of the same
type and rating. The fuse is in a compartment built into the AC inlet of
the amplifier and can be accessed by opening the fuse compartment with
a small flat-head screwdriver or similar tool. In order to change the