User Manual

Introduction
The revolutionary aspect of Class J is its ability to combine ultra high efficiency of 99% with extraordinary bass control. Class J
is an evolution on PWM (Class D) technology that combines advanced multi-level digital feedback with an intelligent controller.
It modulates the supply voltage and output switching frequency in real time based on the frequency and amplitude content of
the input signal. This added level of intelligence offers several advantages such as increased thermal headroom, dramatically
improved bass response and dynamic power capabilities.
The patented Class J output stage ensures stellar audio quality and takes the
concept of the “intelligent circuit” a step further by actually adapting the electri-
cal operation of the output stage to the signal it is playing. This can rightly be
considered a quantum leap in amplifier technology.
Fig.1 Diagram of the Class J Principle
VE-TAT (Velocity Enhancing Transistor Augmentative Technology ) is an
enhanced transistor dead-time controller. Where Class J is an intelligence
infused output topology, VE-TAT works at the component level. A critical area
for efficiency in a PWM (switching output) amplifier is the speed and precision
by which the transistors can be opened and closed. VE-TAT dramatically
increases transistor velocity thus eliminating dead-time losses and increasing
efficiency.
Thank you for purchasing this XJ-700R LFE Mono Block Class J Amplifier. Designed to exceed all of your expectations for audio
amplification, the XJ-700R is a ruggedly constructed high quality profesional amplifier equally suited for home or professional
use. It is ideal for heavy duty sub-woofer application, powerhouse for multiple tactile transducers, and a variety of other home
and studio applications.
TheThe XJ-700R is a high power mono block subwoofer amplifier ideal for powering large subwoofers or tactile transducers.
Featuring advanced Class J output technology, VE-TAT acceleration and MARS protection - all in a cool running fan free 1U
package. Sporting 700/400 WRMS into 4/8 ohm, the XJ700R is ready to power your low frequency needs. The XJ-700R has
optimized presets for movie/ music listening, a digital volume readout with rotary dial and remote control.
Features include : variable low pass filter, phase inversion and precalculated boundary EQ.
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