A Word From The President - EarthQuake XJ-1000FR User Manual

First of all, thank you for purchasing this XJ-1000FR power
amplifier. The multi-patented series of XJ power amplifiers
employs some of the most advanced
technologies ever made.
The XJ amplifiers deliver more sound using less power - in
line with today's energy conservation trend. Right of the
get go, you can see that the XJ amplifiers are light, small
and have no noisy fans. It converts with record efficiency
power from the "wall outlet" to "music in your ears".
For years, there have been many attempts to make high
efficiency amplifiers using Pulse Width Modulated (PWM)
output; PWM amplifiers are also known as class "D"
amplifiers - referred to as digital amplifiers. For the most
part, these technologies suffered from several issues:
1- Could not handle full range signals, so these amplifiers
worked only for subwoofer applications.
2- some class "D" were designed to operate in full range,
this is common in the pro-sound market where the high
power applications masked the high level of distortion
produced by the amplifier. For home audio, the high speed
switching PWM radiated out of the amplifier and effected
other equipments surrounding it.
So how did we do it?
Earthquake Sound Corporation, an engineering driven
company, lead for over 26 years the field of audio
innovations. A plethora of audio patents is proof that we
constantly stay at the cutting edge of technology.
Leading the way means that we can not take the "easy
route" of using off the shelf hybrid chips: generic "me too"
solutions or other compromises. We blazed the trail with
From our hands to your ears... Thank you.
Your Brother In Sound
President & Chief Engineer
Joseph J. Sahyoun;
www.earthquakesound.com
real innovations and real technology invented right here in
the USA, by hardworking and dedicated engineers.
GREEN
The XJ-1000FR is constructed upon a novel PWM power
supply that delivers DC power at an incredible 99.5%
efficiency. The DC power is
amplifier with the necessary energy to reproduce clear,
powerful output.
The power supply uses more than 6 layers of copper-clad
PCB to control and fully ground high frequency radiations.
The output circuitry employs its own PWM stage to deliver
clean accurate sound. A sound quality so good that it rivals
the best of class AB designs
The input audio stage employs a digital signal processor
(DSP) to shape and control the
compromising signal / noise ratio or separation. The DSP
also controls the sophisticated DCDC (dynamic control
drive circuitry) that regulates the DC power so it is just "a
notch"above the need of the amplifier - based on the audio
signal while maintaining low THD and noise.
The XJ FR line is designed with an advanced multi-path
digital feedback system that connects and optimize the
audio analog input, the audio PWM output, and the PWM
power supply in an "on time" balanced relationship.
I hope that you will enjoy this amplifier, we worked hard to
perfect it. We will value any feedback you might have on its
performance and design.
Thank you for choosing Earthquake.
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A Word From The President

used to feed the output
signal without
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