EarthQuake XJ-600R User Manual

DIGITAL FEEDBAC K C L A S S “ J ” M O N O B LOCK AMPLIFIER

USERS MANUA L

www.earthquakesound.com

XJ-600R

MODEL

Sound That Will Move You

The is capable of generating high sound
pressure levels. You should exercise caution when

operating this amplifier system. Long term
exposures to high levels of sound pressure will cause
permanent damage to your hearing. Sound pressure levels
exceeding 85dB can be dangerous with constant exposure. Set
your audio system to a comfortable loudness level. Earthquake
Sound Corporation does not assume liability for damages
resulting from the direct use of the XJ-600R , and urges users to
play the XJ-600R at moderate listening levels.

XJ-600R

THE CHA RT (ON THE SIDE ) SHO WS TH E U.S . GOV ERN MEN TS

OCCUPATI ONA L SAF ETY AN D HEA LTH ADM INI STRATIO N (OS HA)

REGUL ATIONS WHICH WERE I N EFF ECT AT TH E TIM E OF TH IS

PUBLI CATION FOR PER MIS SIB LE NO ISE E XPO SUR E,

PER 29C FR1 910 .95 , TABL E G-1 6.

97
100
102

105
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11 5

3
2
1 - 1 1/2

1
1/ 2
1/ 4 or l es s

SOU ND L EV EL

DBA

90
92
95

8
6
4

DUR AT IO N

IN HO UR S

Congratulations and thank you for choosing the new Earthquake XJ-600R
Subwoofer Power Amplifier as a key component for your audiophile system.
The XJ-600R amplifier is designed to meet the highest standards of
performance and sound quality. In addition, Earthquake Sound’s IQ certification
and patented Class “J” circuitry ensures that the amplifier meets and exceeds all
industry standards. The new XJ-600R amplifiers include many unique
technologies that allow it to deliver “World Class” performance, even under
extreme operating conditions.

The XJ-600R is a ruggedly constructed high quality professional amplifier. The
Digital feedback class “J” Circuitry, allows the amplifier to produce massive
amounts of power with minimal heat production. This patented circuitry delivers
high efficiency in the range of 99%- The typical class AB amplifier runs at about
40 to 50%.

The XJ-600R offers a room correction technique that surpasses that of all
previous attempts. The intelligent “Back EMF” drive circuit interacts with the
subwoofer design and memorizes system tuning frequencies and system type.
The information which is stored in microprocessor turns on a preset group delay
curve that serves as a correction reference. This information deals only with
time correction that moves the peaks and the dips in a room to a flat. Once that is
achieved the user will resort to the final correction- EQ the room. For that reason
Earthquake’s XJ-600R is truly an intelligent system. 20Hz, 30Hz and 40Hz
frequencies can be cut or boosted by a whopping 12dB, these corrections help
in producing wider range of listening position that is unprecedented for the
room.

(Note: boosting the response at 20Hz is very demanding for your subwoofer.
Consult with your subwoofer maker, and determine if their subwoofer is
designed to take a boost at such low frequencies.)

Introduction

2

CAUTION:

Specific ation s Are Subject To Chan ge Wi thout Noti ce

XJ-600R Subwoofer Power Amplifier

Unpacking and Warnings

Speci fications & featu res are s ubjec t to change without n otice . www.earthquakesound .com

3

ITEMIZED LIST OF INCLUDED ACCESSORIES:

1. One (1) AC Power Cable

2. One (1) Users Manual

3. One (1) Registration/Warranty Card

4. One (1) Remote Control

4. Rack Mounting Brackets and Screws

When you have safely removed the amplifier from the packaging and placed it in a safe area, perform a thorough physical inspection and report any damage to the dealer
that you purchased the unit from. We suggest that you keep the original packaging, and that it should be stored in a safe, dry place in case you’re required to transport the
unit. The customized packaging is specially designed to protect the amplifier from potential damage that can arise when shipping such a product.

To reduce the risk of fire or electric shock, do not expose this product to rain or moisture. Don not attempt to “lift the ground” by removing
the ground pin from the AC cable. Make sure that your household electrical wiring supports proper AC grounding techniques before
plugging in this product. Keep the heat sinks and top cover free of dust to allow for proper heat dissipation. Never expose this product to
extreme temperature. Always connect the audio signal path cable prior to connecting the AC mains.

WARNING!

CAUTION!

No user-serviceable parts inside. Do not attempt to remove cover or repair this product, as severe electrical shock may result and it may
disrupt your warranty.

IMPORTANT!

Make sure that your local AC voltage complies with the unit’s label. Damage caused by plugging this amplifier into an AC receptacle of the
wrong voltage will not be covered by warranty.

Specific ation s Are Subject To Chan ge Wi thout Noti ce

XJ-600R Subwoofer Power Amplifier

Subwoofer Placement Guide

Why having two gains on a mono subwoofer is
a good thing?

Often you hear the term “subwoofers are non-directional”;
this is not true subwoofer placement is harder to pick when to
low frequencies are crossed . The wider the room, the more
directional the subwoofer. The easiest solution is to use two
subwoofers in the front: one on the left and a second on the
right. The signal to both is mono. In some applications, users
might have small front speakers or planer speakers. Both
speakers have an early roll off in the sub-harmonics. The
planer needs help from 150Hz on down, having two front
subwoofers placed on the left and the right is a health
solution to this problem.

Two Subs

While having two subwoofers is better than one, the MONO
signal that drives these subwoofers keeps them from
projecting the three dimensional images in the sub­harmonics. The use of two subwoofers allows you to cross
the sub up to 150 Hz sound quality, imaging and staging. The
two-front-subwoofer-system is an excellent solution to planer
speaker’s low frequency response early roll off. When
locating these subwoofers in a close proximity to the stereo
satellite, the subs will enhance low frequency extention. It
will be better to have a stereo subwoofer to help in the lower
bass notes and their placement.

If a bass Guitar player was standing on the left side of the
stage, and he played an EE note (42Hz) then the right sub will
also respond to that and create havoc on the stage. This can
occur if you only have one single sub in the room and it’s
placed on the right side of the room, while the bass guitar
player is playing his music on the left side of the stage. As
soon as he hits the EE note the sub speaks out on the right
and completely destroys the stage. To give you three­dimensional front-end bass that allows you to have a low
frequency dynamic stage, Earthquake designed dual input
circuits that use buffers to maintain your stereo separation on
the processor side while mixing stereo front signals to
produce 3D bass.

Th e blue ar ro w represents th e sub-harmoni c
frequen cies as they mo ve a lways tow ard the
middle in a m ono-t wo-subs - syste m.

The re d ar ro w re present the lows+ the mids+ highs
as they fol low the a ction.

Note the br eakaw ay and the im age sep aration

BETTER / Th is illu stratio n shows d ual subwo ofer wi th mono sig nal

4

In this illustra tion th e st ereo su bw oofer s keep the
sub - h arm o nic s dyn a mic a l ly s ync h r oni z ed i n
motion wi th the re st of the aud io syst ems.

Fully compl ement ar y su b-har monics to the mids
and the hig hs

BEST / Th is illu stratio n shows d ual subwo ofers w ith stere o+mon o signals

GOOD / This i llust ration sh ows a sin gle subwo ofer se tup

Th e b lue a rro w rep re sen ts th e s ub har mo nic
frequen cies as they m ove always towa rd t he sub in
the singl e sub sys tem.

The red arrow rep resen ts t he l ows+ mids + hi ghs as
they foll ow the ac tion.

Note the br eakaw ay and the im age sep aration .

Best resp onse if t he blue and t he red ar e identic al.

Specific ation s Are Subject To Chan ge Wi thout Noti ce

XJ-600R Subwoofer Power Amplifier