Owner`s manual

JamVOX Effect guide
2
About the Gain and Volume knobs
JamVOX’s amp models provide three programmable knobs that affect the volume (gain); GAIN, VR GAIN, and OUTPUT. Each control has its own
specific job, and the sound of a particular amp model can vary over an amazingly wide range just depending on the settings of these knobs.
As some of you will know, most vintage amps only have one VOLUME control to set up the sound, whilst more modern amps usually have two
types of level controls — GAIN (or sometimes PREAMP VOLUME) that controls the input level of the preamp section, and MASTER VOLUME
that controls how much signal is (and how loud it is going to be) passed from the preamp to the power amp. With many vintage amps there is no
MASTER VOLUME, the preamp feeds directly into the power amp without any type of control.
The JamVOX’s controls are designed to cover all these points:
JamVOX GAIN: On vintage type models that do not have a master volume (i.e., AC15, AC15TB, AC30, AC30TB, UK BLUES, UK 68P, BLACK 2x12,
TWEED 1x12, TWEED 4x10), the GAIN control works like the VOLUME of the original amp. On models that do have a master volume, the GAIN
control works like GAIN or PREAMP VOLUME.
JamVOX VR GAIN: MASTER VOLUME that controls how much preamp signal level is passed to the power amp, which in our case is the VIR-
TUAL VALVE REACTOR stage. (Your JamVOX works like a real amp.)
JamVOX OUTPUT : For want of a better way of putting it, this is like a power attenuator that you would add between the output of your amp and
the input of your speaker cabinet.
As in how the original amps work, we have made the relationship between preamp and power amp work in the same way. Therefore to obtain
truly authentic tones please use the VR GAIN control in the same way, i.e. with VINTAGE type models that do not have Master Volume control’s,
turn the VR GAIN control up to maximum.
When using a model of a modern amp that does have a master volume control, adjust VR GAIN just as you would adjust the master volume con-
trol. Low settings of VR GAIN will tend to produce more of a preamp distortion, while high settings will add the distinctive distortion and warmth
of the Valve Reactor.
Lastly, if an original amp features a unique switch or control we make sure that we cover it! Such things will be revealed in the model descriptions
that follow shortly...
Virtual Valve Reactor
Valve Reactor technology was first used in the VOX AD60/120VT amps. In the ToneLab series, this consisted of a low-wattage tube power amp cir-
cuit, a virtual output transformer that used solid-state components to emulate an output transformer, and a dummy speaker circuit that simulated
the impedance changes of a speaker. Virtual Valve Reactor turns this Valve Reactor technology completely into software, simulating the same cir-
cuit structure as a real full-tube amp.