Earthquake Sound IQ1500 User Manual

Introduction

IQ Subwoofer Power Amplifier

Congratulations and thank you for choosing the new Earthquake

IQ1500 IQ1500

Subwoofer Power Amplifier as a key component for your audiophile system.

IQ1500

The 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 ensure that the amplifier meets and exceeds all industry
standards. The new amplifiers include many unique technologies that

IQ1500
allow it to deliver “World Class” performance, even under extreme operating
conditions.

IQ1500

The 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 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 is truly an intelligent system. 20Hz, 30Hz and 40Hz

IQ1500

frequencies can be cut or boosted by a whopping 6dB, 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.)

SOU N D L E VE L

DBA

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DURAT IO N

IN HO U R S

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THE CH ART (ON THE S IDE) SH OWS T HE U.S. G OV ERN MENTS

OCCU PATI ONAL SAFET Y AND HEA LTH A DMINI STRATION ( OSH A)

REGU LATI ONS WHI CH WERE IN EFF ECT AT T HE TIME O F THIS

PUBLIC ATIO N FOR PER MISSIBLE N OISE EX POSURE,

PER 29 CFR19 10.95, TABLE G-1 6.

Specifications Are Subject To Change Without Notice

CAUTION:

The IQ1500 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 IQ1500 , and urges users to
play the IQ1500 at moderate listening levels.

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IQ Subwoofer Power Amplifier

ITEMIZED LIST OF INCLUDED ACCESSORIES:

1. One (1) AC Power Cable

2. One (1) Users Manual

3. One (1) Registration Card

4. One (1) Remote Control

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.

Unpacking and Warnings

WARNING!

CAUTION!

IMPORTANT!

Specifications Are Subject To Change Without Notice

Specifications & features are subject to change without notice. www.earthquakesound.com

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.

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.

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.

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Subwoofer Placement Guide

IQ Subwoofer Power Amplifier

GOOD / T his illustration show s a single s ubwoofer setup

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 subwoofer 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.

The blue arrow represents the subharmonic
frequencies as they move always toward the sub in
the single sub system The red arrow represents the
lows+ mids+ highs as they follow the action Note
the breakaway and the image separation. Best
response if the blue and the red are identical

BETTER / T his illustration show s dual subwoofer with mon o signal

The blue arrow represents the sub-harmonic
frequencies as they move always toward the
middle in a mono-two-subs- system The red arrow
represent the lows+ the mids+ highs as they follow
the action, Note the breakaway and the image
separation

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. In fact 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.

Specifications Are Subject To Change Without Notice

BEST / T his illustration show s dual sub woofers with stereo+m ono signals

In this illustration the stereo subwoofers keep the
sub-harmonics dynamically synchronized in
motion with the rest of the audio systems. Fully
complementary sub-harmonics to the mids and the
highs

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