Vox valve reactor – Vox Valvetronix ToneLab SE User Manual

Page 13

Introduction

Panel Tour

Setup

Playing

Creating

and Storing

Apart from the vital

valve tone this ingenious
power amp design provides, it
also allows us to replicate var-
ious “circuit characteristics”
that are unique to the all-valve
power stages of the amps
we’ve modelled. These “char-
acteristics” include: Class A or
Class AB operation, Presence
and Resonance (low end)
control circuitry (both found in
the negative feedback circuit
that some, but not all, valve
power amps have). Being able
to match such vital characteristics helps ensure that each and every one of our
models is as tonally authentic as possible - as opposed to the usual “close but defi-
nitely no cigar” norm of digital modeling. And just so you know, this patented in
USA power amp technology is unique to VOX Valvetronix.

VOX VALVE REACTOR

FEEDBACK

CIRCUIT

(WITH OR W/O

PRESENCE &

RESONANCE)

REACTOR

AMP

USING

CONSTANT

CURRENT &

REACTIVE

FEEDBACK

MODEL

DEPENDENT

12AX7 (DUAL TRIODE)

PUSH–PULL OUTPUT

PREAMP

VIR

AL OUTPUT

TRANSFORMER

CLASS A OR AB

MODEL DEPENDENT

PHASE

INVERTER

DUMMY

SPEAKER

12AX7

(ECC83)

12AX7

(ECC83)

BIAS