MartinLogan Monolith III User Manual

User's Manual

The Monolith III Speaker System

Important

Your Martin-Logan speakers are
provided with automatic Limited 90
Day Warranty coverage.

Contents

Introduction

3

You have the option, at no additional
charge, to receive Limited 3 Year
Warranty coverage. To obtain Limited 3
Year Warranty coverage you need only
complete and return the

Registration

your speakers to Martin-Logan, within
30 days of purchase.

If you did not receive a Certificate of
Registration with your speakers, you
cannot be assured of having received
new units. If this is the case, please
contact Martin-Logan.

We know you are anxious to listen to
your new speakers. So, to speed you
along, we have provided an Installation
in Brief section ahead of the detailed
descriptive information contained in
this manual.

Please read and follow these instruc­tions for installation in brief as you
initially connect your speakers into your
system. These instructions are
important and will prevent you from
experiencing any delay, frustration, or
system damage which might occur in
a trial-and-error procedure.

The other sections of your User’s
Manual will explain in detail the
operation of your speakers and the
philosophy applied to their design. A
clear understanding of your speakers
will insure that you obtain maximum
performance and pleasure from this
most exacting transducer.

that was included with

Certificate of

Installation in Brief

Monolith III Specifications

History

Connection

IIIp Connection

IIIx Connection

IIIx Operation

IIIx Technical Description

Room Acoustics

Placement

General Information

The Electrostatic Concept

Martin-Logan Exclusives

Questions

Troubleshooting

Glossary

4

5

6

8

9

12

14

16

18

21

23

24

26

28

29

30

Page2

Monolith III User's Manual

Introduction

Congratulations, you have invested in
one of the world’s premier loudspeaker
systems!

The Martin-Logan MONOLITH III repre­sents the culmination of an intensive,
dedicated group research program
directed toward establishing a world
class reference monitor utilizing
leading-edge technology, without
compromising durability, reliability,
craftsmanship, or aesthetic design.

The original Monolith made its official
debut in June of 1982 at the Interna­tional Consumer Electronics Show
where it was selected for the prestigous

Design and Engineering Exhibition

one of the most innovative consumer
electronics products of that year. Since
then, the Monolith has become the
speaker of choice by the most demand­ing musicians, electronics manufactur­ers, and recording studios, as well as
the most discerning critical listeners.

As a result of our continuous research
and development program here at
Martin-Logan, we decided that it was
time to incorporate some of our latest
technologies into the already outstand­ing Monolith. So, in January of 1990 we
introduced the MONOLITH III to the
marketplace.

With the MONOLITH III, we have ad-
vanced the current state of the art in

as

many areas of loudspeaker design.
Bass response has better extension,
superior impact and improved defini­tion, high frequency response also has
better extension and is much more
natural in character. Much effort was
spent on minimizing all diffractive or
reflective surfaces. This has improved
overall transparency and image quality.

In addition, a great amount of energy
was spent on the interface between the
electrostatic element and the woofer,
with astonishing results. The fruit of this
labor has brought us the passive IIIp

INTERFACE and the superior electronic
IIIx CROSSOVER. With either of these two

devices, the transition from the electro­static element to the woofer becomes
invisible and an unbelieveable continu­ity of sound prevails. With the IIIx

CROSSOVER

you are brought even closer to the
musical truth. Dynamic information
suddenly becomes frightening. Power
handling and system efficiency are
enhanced as well.

Like the original Monoliths, all materials
in your new MONOLITH III speakers are
of the highest quality to provide years of
enduring enjoyment and deepening
respect. All trim pieces are constructed
from selected hardwoods. They are
then grain and color matched and finally
hand finished. The cabinetry is con­structed from a special high-density

another veil is lifted and

hardwood powderboard for structural
integrity and is finished with a durable
and attractive leatherette.

Through rigorous testing, the curvilinear
electrostatic panel manufactured and
used by Martin-Logan has proven itself
to be one of the most durable and
reliable transducers available today.
Fabricated from a specially tooled, high­grade steel, the panel is then coated
with a special high dielectric nylon/
Delrin based polymer that is applied via
a proprietary electrostatic deposition
process. This panel assembly houses
a membrane 0.0005 of an inch thick!
Ruggedly constructed and insulated, as
much as 200 watts of continuous
power has driven the MONOLITH III's
energized diaphragm into massive
excursions with no deleterious effects.

We again thank you for purchasing the

MONOLITH III. By following the Installa-
tion in Brief instructions you may

connect them to your system, sit back,
relax, and enjoy this most exacting
transducer. It has been designed and
constructed to give you years of trouble­free listening enjoyment.

Happy Listening!

Monolith III User's Manual

Page3

Installation in Brief

We know you are eager to hear
your new MONOLITH III loudspeak­ers, so this section is provided to
allow fast and easy set up. Once
you have them operational, please
take the time to read, in depth, the
rest of the information in this
manual. It will give you perspective
on how to obtain the best possible
performance from this most
exacting transducer.

If you should experience any
difficulties in the set-up or opera­tion of your MONOLITH III speakers
please refer to the Room Acoustics,
Placement or Connection section
of this manual.

Should you encounter a persistent
problem that cannot be resolved,
please contact your Authorized
Martin-Logan dealer. He will
provide you with the appropriate
technical analysis to alleviate the
situation.

Step 1: PlacementStep 1: Placement

Step 1: Placement

Step 1: PlacementStep 1: Placement

Place each Monolith at least two feet from any wall and slightly angle them
toward your listening area. This is a good place to start. Please refer to the
Room Acoustics and Placement sections of this manual for more details.

Step 2: PStep 2: P

Step 2: P

Step 2: PStep 2: P

Martin-Logan Monoliths require AC power to energize their electrostatic cells.
Using the AC power cords provided, plug them in, making sure that you have
made a firm connection, first to the AC power receptacle on the rear panel of
the speaker and then to the wall outlet. Extension cords may be used, if
necessary, since the AC power requirement of the Monolith is extremely small.

Step 3: Signal ConnectionStep 3: Signal Connection

Step 3: Signal Connection

Step 3: Signal ConnectionStep 3: Signal Connection

Turn your amplifier off before making or breaking any signal connections!

The chassis is earth grounded and can present a short circuit to your

ower Connection (Aower Connection (A

ower Connection (A

ower Connection (Aower Connection (A

WARNING !WARNING !

WARNING !

WARNING !WARNING !

amplifier if contact is made!

C)C)

C)

C)C)

Page4

Use the best speaker cables you can! 16 gauge zip-cord is the minimum you
should use, and higher quality cables, available from your specialty dealer, are
recommended and will give you superior performance! Spade or banana
connectors are suggested for optimum contact and ease of installation.

Be consistent when connecting speaker leads to the terminals on the back of
the MONOLITH III: take great care to assign the same color to the (+) terminal on
both the left and right channels. If bass is nonexistent and you cannot discern a
tight, coherent image, reverse the (+) and (-) leads on one side to bring the
system into proper polarity. Attach your speaker cables to the Amplifier Signal
input section of the IIIp INTERFACE if you have the MONOLITH IIIp
appropriate Signal Input section on the back of the MONOLITH III if you are using
the MONOLITH IIIx CROSSOVER. Please refer to the appropriate Connection
section of this manual for further details and instructions.

Step 4: Listen and EnjoyStep 4: Listen and Enjoy

Step 4: Listen and Enjoy

Step 4: Listen and EnjoyStep 4: Listen and Enjoy

Now, you may turn on your system and enjoy!

or directly to the

Monolith III User's Manual

Monolith III Specifications

The MONOLITH III hybrid speaker
system consists of a broad-range
single element electrostatic transducer
integrated with a quick-response
woofer. This approach takes maximum

MONOLITH III SPEAKER

System Frequency ResponseSystem Frequency Response

System Frequency Response

System Frequency ResponseSystem Frequency Response

28-24,000 Hz +/-2dB

Electrostatic Frequency ResponseElectrostatic Frequency Response

Electrostatic Frequency Response

Electrostatic Frequency ResponseElectrostatic Frequency Response

95-24,000 Hz +/- 2dB

Woofer Frequency ResponseWoofer Frequency Response

Woofer Frequency Response

Woofer Frequency ResponseWoofer Frequency Response

28-2,000 Hz +/- 2dB

DispersionDispersion

Dispersion

DispersionDispersion

Horizontal: 30 Degrees
Vertical: 4' Line Source

SensitivitySensitivity

Sensitivity

SensitivitySensitivity

89dB/2.83 Volts/meter

advantage of the positive aspects that
both technologies have to offer.

Dispersion is a controlled 30 degrees.
This was achieved by curving the

ImpedanceImpedance

Impedance

ImpedanceImpedance

High-pass:High-pass:

High-pass:

High-pass:High-pass:

Nominal: 4 ohms, below 10kHz
Minimum: 1 ohm @ 20kHz

Low-pass:Low-pass:

Low-pass:

Low-pass:Low-pass:

Nominal: 4 ohms
Minimum: 4 ohms

Power HandlingPower Handling

Power Handling

Power HandlingPower Handling

250 watts per channel

Recommended Amplifier PowerRecommended Amplifier Power

Recommended Amplifier Power

Recommended Amplifier PowerRecommended Amplifier Power

80 - 250 watts per channel

electrostatic transducer element itself,
an elegantly simple solution.

WeightWeight

Weight

WeightWeight

120 lbs/speaker; 54.4 kg/speaker

Size Size

Size (HWD)

Size Size

73.75" x 26.75" x 11.75"

187.3cm x 67.9cm x 29.8cm

ComponentsComponents

Components

ComponentsComponents

Glass-epoxy boards,
custom-wound audio transformers,
30-amp gold plated binding posts,
regulated HV power supply

IIIp INTERFACE

Crossover FrequencyCrossover Frequency

Crossover Frequency

Crossover FrequencyCrossover Frequency

125 Hz @ 12dB/octave

ImpedanceImpedance

Impedance

ImpedanceImpedance

Nominal: 4 ohms, below 10kHz
Minimum: 1 ohms @ 20kHz

ComponentsComponents

Components

ComponentsComponents

Glass-epoxy boards,
polypropylene capacitors,
100% OFC coils,
wirewound resistors,
30-amp gold plated binding posts,
non-ferrous enclosure

Monolith III User's Manual

IIIx CROSSOVER

Crossover FrequencyCrossover Frequency

Crossover Frequency

Crossover FrequencyCrossover Frequency

125 Hz: @12dB/octave low-pass

@18dB/octave high-pass

Input ImpedanceInput Impedance

Input Impedance

Input ImpedanceInput Impedance

47,000 ohms

Output ImpedanceOutput Impedance

Output Impedance

Output ImpedanceOutput Impedance

100 ohms

DistortionDistortion

Distortion

DistortionDistortion

0.003% THD @ 1kHz @ 1Vrms

Signal to NoiseSignal to Noise

Signal to Noise

Signal to NoiseSignal to Noise

Greater than -95dB

Circuit TopologyCircuit Topology

Circuit Topology

Circuit TopologyCircuit Topology

Audio circuits are fully complimen­tary, class-A current-biased J-FET
buffers that isolate passive filter
networks.

Power supply employs a toroidal
transformer , discrete voltage and
self-tracking current regulation.
40-volt peak to peak swing allows
for 30dB of dynamic headroom.

ComponentsComponents

Components

ComponentsComponents

Glass-epoxy boards, metal film
resistors, polypropylene capacitors,
hand picked J-FETs,
input/output connectors

TIFFANY

Page5

History

In the late 1800’s, any loudspeaker was
considered exotic. Today, most of us
take the wonders of sound reproduction
for granted.

It was 1880 before Thomas Edison had
invented the first phonograph. This was
a horn-loaded diaphragm that was
excited by a playback stylus. In 1898, Sir
Oliver Lodge invented a cone loud­speaker, which he referred to as a
“bellowing telephone”, that was very
similar to the conventional cone
loudspeaker drivers that we know today.
However, Lodge had no intention for his
device to reproduce music, because in
1898 there was no way to amplify an
electrical signal! As a result, his
speaker had nothing to offer over the
acoustical gramophones of the period.
It was not until 1906 that Dr. Lee
DeForrest invented the triode vacuum
tube. Before this , an electrical signal
could not be amplified. The loud­speaker, as we know it today, should
have ensued then, but it did not.
Amazingly, it was almost twenty years
before this would occur.

In 1921, the electrically cut phonograph
record became a reality. This method of
recording was far superior to the
mechanically cut record and pos­sessed almost 30 dB of dynamic
range. The acoustical gramophone
couldn't begin to reproduce all of the
information on this new disc. As a
result, further developments in loud­speakers were needed to cope with
this amazing new recording medium.

By 1923, Bell Telephone Laboratories
made the decision to develop a
complete musical playback system
consisting of an electronic phonograph

and loudspeaker to take advantage of
the new recording medium. Bell Labs
assigned the project to two young
engineers, C.W. Rice and E.W. Kellogg.

Rice and Kellogg had a well equipped
laboratory at their disposal. This lab
possessed a vacuum tube amplifier
with an unheard of 200 watts, a large
selection of the new electrically cut
phonograph records and a variety of
loudspeaker prototypes that Bell Labs
had been collecting over the past
decade. Among these were Lodge’s
cone, a speaker that used compressed
air, a corona discharge (plasma)
speaker, and an electrostatic speaker.

After a short time, Rice and Kellogg had
narrowed the field of “contestants”
down to the cone and the electrostat.
The outcome would dictate the way that
future generations would refer to
loudspeakers as being either “conven­tional”, or “exotic”.

Bell Laboratory’s electrostat was
something to behold. This enormous
bipolar speaker was as big as a door.
The diaphragm, which was beginning
to rot, was made of the membrane of a
pigs intestine that was covered with fine
gold leaf to conduct the audio signal.

When Rice and Kellogg began playing
the new electrically cut records through
the electrostat, they were shocked and
impressed. The electrostat performed
splendidly. They had never heard
instrumental timbres reproduced with
such realism. This system sounded
like real music rather than the honking,
squawking rendition of the acoustic
gramophone. Immediately, they knew
they were on to something big. The

acoustic gramophone was destined to
become obsolete.

Due to Rice and Kelloggs enthusiasm,
they devoted a considerable amount of
time researching the electrostatic
design. However, they soon encoun­tered the same difficulties that even
present designers face; planar speak­ers require a very large surface area to
reproduce the lower frequencies of the
audio spectrum. Because the manage­ment at Bell Labs considered large
speakers unacceptable, Rice and
Kelloggs work on electrostatics would
never be put to use for a commercial
product. Reluctantly, they advised the
Bell management to go with the cone.
For the next thirty years the electrostatic
design lay dormant.

During the Great Depression of the
1930's, consumer audio almost died.
The new electrically amplified loud­speaker never gained acceptance, as
most people continued to use their old
Victrola-style acoustic gramophones.
Prior to the end of World War II, con­sumer audio saw little, if any, progress.
However, during the late 1940's, audio
experienced a great rebirth. Suddenly
there was tremendous interest in audio
products and with that, a great demand
for improved audio components. No
sooner had the cone become estab­lished than it was challenged by
products developed during this new
rebirth.

In 1947, Arthur Janszen, a young Naval
engineer, took part in a research project
for the Navy. The Navy was
interested in developing a better
instrument for testing microphone
arrays. The test instrument needed an

Page6

Monolith III User's Manual

extremely accurate speaker, but
Janszen found that the cone speakers
of the period were too nonlinear in
phase and amplitude response to meet
his criteria. Janszen believed that
electrostats were inherently more linear
than cones, so he built a model using a
thin plastic diaphragm treated with a
conductive coating. This model
confirmed Janszen's beliefs, for it
exhibited remarkable phase and
amplitude linearity.

Janszen was so excited with the results
that he continued research on the
electrostatic speaker on his own time.
He soon thought of insulating the
stators to prevent the destructive effects
of arcing. By 1952 he had an electro­static tweeter element ready for
commercial production. This new
tweeter soon created a sensation
among American audio hobbyists.
Since Janszen's tweeter element was
limited to high frequency reproduction, it
often found itself used in conjunction
with woofers, most notably, woofers
from Acoustic Research. These
systems were highly regarded by all
audio enthusiasts.

As good as these systems were, they
would soon be surpassed by another
electrostatic speaker.

In 1955, Peter Walker published three
articles on electrostatic loudspeaker
design in

Wireless World

, a British
electronics magazine. In these articles
Walker demonstrated the benefits of the
electrostatic loudspeaker. He explained
that electrostatics permit the use of
diaphragms that are low in mass, large
in area, and uniformly driven over their

surfaces by electrostatic forces. Due to
these characteristics, electrostats have
the inherent ability to produce a wide
bandwidth, flat frequency response with
distortion products being no greater
than the electronics driving them.

By 1956 Walker backed up his articles
by introducing a consumer product, the
now famous Quad ESL. This speaker
immediately set a standard of perform­ance for the audio industry due to its
incredible accuracy. However, in actual
use the Quad had a few problems. It
could not play very loud, it had poor
bass performance, it presented a
difficult load that some amplifiers did
not like, its dispersion was very
directional, and its power handling was
limited to around 70 watts. As a result,
many people continued to use box
speakers with cones.

In the early 1960's Arthur Janszen
joined forces with the KLH loudspeaker
company and together they introduced
the KLH 9. Due to the large size of the
KLH 9, it did not have as many limita­tions as the Quad. The KLH 9 could
play markedly louder and lower in
frequency than the Quad ESL. Thus a
rivalry was born.

Janszen continued to develop electro­static designs. He was instrumental in
the design of the Koss Model One, the
Acoustech, and the Dennesen speak­ers. Roger West, the chief designer of
the JansZen Corporation became the
president of Sound Lab. When JansZen
Corporation was sold, the RTR
loudspeaker company bought half of
the production tooling. This tooling was
used to make the electrostatic panels

for the Servostatic, a hybrid electrostatic
system that was Infinity's first speaker
product. Other companies soon
followed; each with their own unique
applications of the technology. These
include Acoustat, Audiostatic, Beverage,
Dayton Wright, Sound Lab, and Stax to
name a few.

Electrostatic speakers have pro­gressed and prospered because they
actually do what Peter Walker claimed
they would. The limitations and prob­lems experienced in the past were not
inherent to the electrostatic concept.
They were related to the applications of
these concepts.

Today, these limitations have been
addressed. Advancements in materials
due to the U.S. space program give
designers the ability to harness the
superiority of the electrostatic principle.
Todays electrostats use advanced
insulation techniques or provide
protection circuitry. The poor dispersion
properties of early models have been
addressed by using delay lines,
acoustical lenses, multiple panel arrays
or, as in our own products, by curving
the diaphragm. Power handling and
sensitivity have been increased.

These developments allow the con­sumer the opportunity to own the
highest performance loudspeaker
products ever built. It's too bad Rice and
Kellogg were never able to see just how
far the technology would be taken.

Monolith III User's Manual

Page7

Connection

AC Power ConnectionAC Power Connection

AC Power Connection

AC Power ConnectionAC Power Connection

Electrostatic speakers use an internal power supply to
energize their electrostatic elements with high-voltage DC
(low current). As such, they must be connected to an AC
wall outlet. For this reason we have provided your speakers
with the proper IEC standard power cords. These cords
should be firmly inserted into the AC power receptacles on
the rear connection panel of the speakers, then to any
convenient AC wall outlet. Extension cords may be used, if
necessary, since the AC power requirement of the speaker
is extremely small (less than 2.5 watts).

We do not recommend the use of "super cords", as many
of these designs eliminate the ground prong of the male
plug and therefore do not follow IEC convention standards.
If proper plugs are fitted, then the choice is up to you.

Your Martin-Logan speakers have been designed to
remain on continuously and should remain connected to a
continuous AC power source. As mentioned earlier, power
consumption of the MONOLITH III is very small and the life
expectancy of its components will not be reduced by
continuous operation.

The power cord should not be installed, removed,The power cord should not be installed, removed,

The power cord should not be installed, removed,

The power cord should not be installed, removed,The power cord should not be installed, removed,

or left detached from the speaker while the otheror left detached from the speaker while the other

or left detached from the speaker while the other

or left detached from the speaker while the otheror left detached from the speaker while the other

end is connected to an AC wall outlet.end is connected to an AC wall outlet.

end is connected to an AC wall outlet.

end is connected to an AC wall outlet.end is connected to an AC wall outlet.

Your Martin-Logan speakers are wired for the power
service supplied in the country of original consumer sale
unless manufactured on special order. The AC power
rating applicable to a particular unit is specified both on the
packing carton and on the serial number plate attached to
the speaker.

If you remove your Martin-Logan speakers from the country
of original sale, be certain that AC power supplied in any
subsequent location is suitable before connecting and
operating the speakers. Substantially impaired perform­ance or severe damage may occur to a Martin-Logan
speaker if operation is attempted from an incorrect AC
power source.

If your home is not equipped with three-prong wall outlets,
you may use “cheater” plugs to connect the speakers to AC
power. However, please make certain that you connect the
grounding wire or tab of the plug to a ground. These may
be obtained at your dealer or any hardware department.

Signal ConnectionSignal Connection

Signal Connection

Signal ConnectionSignal Connection

Use the best speaker cables you can! The length and type
of speaker cable used in your system will have an audible
effect. Under no circumstance should a wire of gauge
higher (thinner) than #16 be used. In general, the longer
the length used, the greater the necessity of a lower gauge,
and the lower the gauge, the better the sound, with dimin­ishing returns setting in around #8 to #12.

A variety of speaker cables are now available whose
manufacturers claim better performance than with standard
heavy gauge wire. We have verified this in some cases,
and the improvements available are often more noticeable
than the differences between wires of different gauge.

We would also recommend, if possible, that short runs of
speaker cable connect the power amplifier(s) and speak­ers and that high quality long interconnect cables be used
to connect the preamplifier and power amplifier. This
results in the power amplifiers being close to the speakers,
which may be practically or cosmetically difficult, but if the
length of the speaker cables can be reduced to a few
meters, sonic advantages may be obtained. The effects of
cables may be masked if the equipment is not of the
highest quality.

Connections are done at the SIGNAL INPUT section on the
rear electronics panel of the MONOLITH III. Use spade or
banana connectors for optimum contact and ease of
installation. Make certain that all your connections are
clean, tight and positive.

Be consistent when connecting the speaker cables to the
SIGNAL INPUT terminals. Take care to assign the same color
cable lead to the (+) terminal on both the left and right
channel speakers. If bass is nonexistent and you cannot
discern a tight, coherent image, you probably need to
reverse the (+) and (-) leads on one speaker to bring the
system into proper polarity.

The MONOLITH IIIp INTERFACE provides you with three
different methods for connecting the MONOLITH III to your
audio system, while the superior MONOLITH IIIx CROSSOVER
uses active bi-amplification.

Page8

Monolith III User's Manual

IIIp Connection

ONE: Standard Connection for ONE: Standard Connection for

ONE: Standard Connection for

ONE: Standard Connection for ONE: Standard Connection for

Please take note of the jumpers installed
across the binding posts of the IIIp INTER-

..

FACE

. These jumpers attach the high-pass

..
and the low-pass sections of the interface
together. Leaving these in place, connect
the (+) wire from your amplifier to either of
the red AMPLIFIER SIGNAL binding posts of
the Interface and the (-) wire to either of the
black posts. Next, connect the IIIp INTERFACE
to the MONOLITH III with the provided cables.
See

Figure 1.

TWO: Bi-wire Connection for the TWO: Bi-wire Connection for the

TWO: Bi-wire Connection for the

TWO: Bi-wire Connection for the TWO: Bi-wire Connection for the

MONOLITH IIIMONOLITH III

MONOLITH III

MONOLITH IIIMONOLITH III

pp

p.

pp

Figure 1Figure 1

Figure 1: Standard connection for the

Figure 1Figure 1

MONOLITH IIIMONOLITH III

MONOLITH III

MONOLITH IIIMONOLITH III

p.p.

p.

p.p.

MONOLITH IIIp

.

This method of connection replaces the
jumpers installed across the binding posts
of the IIIp INTERFACE with individual runs of
speaker wire from your amplifier. This
doubles the signal carrying conductors from
the amplifier to the speaker thus, direct­coupling each portion of the crossover to the
amplifier.

To bi-wire you must first remove the
jumpers from the IIIp INTERFACE. Connect
one set of wires to the
posts of the IIIp INTERFACE. Then connect a
second set of wires to the
binding posts. Next, connect both sets of
wires to the appropriate terminals on your
amplifier. See
connect both (+) wires to the (+) amplifier
terminals and both (-) wires to the (-)
amplifier terminals. This is known as a
parallel connection.

Monolith III User's Manual

Figure 2

HI+HI+

HI+ and

HI+HI+

. Please take care to

HI-HI-

HI- binding

HI-HI-

LO+LO+

LO+ and

LO+LO+

LO-LO-

LO-

LO-LO-

Figure 2Figure 2

Figure 2: Bi-wire connection for the

Figure 2Figure 2

MONOLITH IIIp

.

Page9

IIIp Connection

THREE: Passive Bi-amplification.THREE: Passive Bi-amplification.

THREE: Passive Bi-amplification.

THREE: Passive Bi-amplification.THREE: Passive Bi-amplification.

The MONOLITH III may be passively bi­amplified using the IIIp INTERFACE.

You cannot use an external electronic
crossover with the
than the
places the

Passive bi-amplification takes the bi­wiring concept one step further. Now
you will have a dedicated channel of
amplification directly connected to the
high and low-pass sections of the
crossover.

There are two different methods to
passively bi-amplify. The first, and
most common, is referred to as
Horizontal Bi-amping. The second
method that is gaining in popularity is
referred to as Vertical Bi-amping. With
either method you may use two stereo
amplifiers, or four mono amplifiers, or
two mono amplifiers and one stereo
amplifier. Get the idea here? With
either form of passive bi-amplification,
your pre-amplifier must have dual

IIIx CROSSOVER

IIIp INTERFACE

MONOLITH III

which re-

)!

(other

outputs. If your pre-amplifier is not so
equipped then you must purchase or
construct a "Y" adapter.

Horizontal bi-amping Horizontal bi-amping

Horizontal bi-amping allows you to

Horizontal bi-amping Horizontal bi-amping
use two different types, models or
brands of amplifiers (i.e. tubes on top,
transistor on the bottom), assuming
that they have identical gain or that one
stereo pair has adjustable gain.

However, we recommend that you use
two identical amplifiers (i.e. same brand
and model). If the ampliers of choice do
not have the same gain characteristics,
then a sonic imbalance will occur
between the high-pass and low-pass
sections of the speaker and integration
between the two will suffer greatly. By
using identical amplification on the
high-pass and the low-pass you will

Page10

Figure 3aFigure 3a

Figure 3a: Horizontal passive bi-amplification connection for the

Figure 3aFigure 3a

Monolith III User's Manual

MONOLITH IIIp

.

eliminate the negative effects of time
delay (also referred to as group delay)
that occurs when a signal passes
through two dissimilar amplifiers. The
very nature of vertical bi-amping
dictates that both amplifiers be identical.

horizontal bi-ampinghorizontal bi-amping

With

horizontal bi-amping, one

horizontal bi-ampinghorizontal bi-amping
amplifier drives the high-pass section
while the second amplifier drives the

low-pass section. To
amp amp

amp your Monoliths you must remove

amp amp

horizontally bi-horizontally bi-

horizontally bi-

horizontally bi-horizontally bi-

the jumpers from the AMPLIFIER SIGNAL
binding postsof the IIIp INTERFACE.
Connect the low frequency amplifier to
the

LO+LO+

LO+ and

LO+LO+

LO-LO-

LO- AMPLIFIER SIGNAL

LO-LO­binding posts of each IIIp INTERFACE.
Connect the high frequency amplifier to
the

HI+HI+

HI+ and

HI+HI+

HI-HI-

HI- binding posts. Next

HI-HI-

connect the left and right preamplifier

outputs to the appropriate left and right
inputs of both amplifiers. See

3a

.

vertical bi-ampingvertical bi-amping

With

vertical bi-amping, each of the

vertical bi-ampingvertical bi-amping

Figure

stereo amplifiers is dedicated to one
speaker. For instance, the left channel
of each amplifier drives the low -pass
section while the right channel drives
the high-pass section. To
amp amp

amp your Monoliths, you must remove

amp amp

vertically bi-vertically bi-

vertically bi-

vertically bi-vertically bi-

the jumpers from the AMPLIFIER SIGNAL
binding posts of each IIIp INTERFACE.
Start by connecting the left amplifier
channel of amplifier #1 to the
LO-LO-

LO- binding posts and the right

LO-LO-

LO+LO+

LO+ and

LO+LO+

amplifier channel of amplifier #1 to the
HI+HI+

HI+ and

HI+HI+

HI-HI-

HI- binding posts of the IIIp

HI-HI­INTERFACE. Then repeat the same
procedure for the other speaker with
amplifier #2. Connect the left preampli­fier outputs to both inputs of the left
channel amplifier (#1) and the right
preamplifier outputs to both inputs of
the right channel amplifier (#2). See

Figure 3b

.

Figure 3bFigure 3b

Figure 3b: Vertical passive bi-amplification connection for the

Figure 3bFigure 3b

Monolith III User's Manual

MONOLITH IIIp

.

Page11

IIIx Connection

IntroductionIntroduction

Introduction

IntroductionIntroduction

The MONOLITH IIIx system utilizes the
electronic IIIx CROSSOVER which
incorporates technology developed for
our STATEMENT SYSTEM CROSSOVER.
Use of the MONOLITH IIIx CROSSOVER
will result in substantial improvements
in all aspects of your system's perform­ance. Bass will be more extended with
more impact and control. Special bass
contour controls allow you to tailor the
bass response to suit your particular
room environment or listening tastes.
The crossover region between the
woofer and electrostatic panel is
optimized, thus making the system
blend much more homogeneous.
Highs are much more extended,
detailed and effortless. The system
becomes much more dynamic with
less strain. To understand why this
occurs, we need to look at the differ­ences between a single amplified
system versus a properly interfaced bi­amplified system.

In a single amplified system, the left
and right full-bandwidth signals pass
from the preamplifier to a stereo power
amplifier (or two mono amplifiers) and
then to the loudspeaker's crossover,
unchanged (we hope) except for
amplitude. Once these signals reach

the crossover of the speaker they are
divided into high and low frequency
signals. The lower frequency signals
are then directed to the woofers, while
the high frequencies are routed to the
electrostatic panels. This is known as a
high-level passive crossover. This
means that the frequency division of the
signal is done after the power amplifier
at high power (several volts) by means
of passive components (capacitors,
resistors, inductors and transformers).

When bi-amplifying with the MONOLITH
IIIx CROSSOVER, the right and left full­bandwidth signals are divided into
separate high and low frequency
signals after the pre-amplifier by means
of an active electronic crossover. These
signals are then fed to dedicated high
and low frequency amplifiers. This is
referred to as a low-level active cross­over, because all frequency division of
the signal is done at line level at very
low power (millivolts) with active
components (transistors).

This configuration has several advan­tages. With the frequency division of the
signal done prior to amplification, each
amplifier has only to contend with

frequencies of a narrow bandwidth,
thus it cannot combine high and low
frequency signals and produce sum
and difference by-products (intermodu­lation distortion or IM). For example, to
reproduce deep bass such as an organ
tone or kick drum, very high power
(current) is needed. Since the low
frequencies have their own dedicated
amplifier, this demand for low frequency
power will not affect the ability of the
high frequency amplifier to perform its
function normally, whereas if all
frequencies were reproduced by the
same amplifier, its power supply might
temporarily be depleted by the deep
bass passage, causing dynamic
compression or clipping of the high
frequency material.

Another added benefit of bandwidth
limiting an amplifier, particularly the
high frequency amplifier, is the slight
increase in dynamic power output that
occurs. The amplifier does not have to
work as hard due to the reduction in the
bandwidth amplification requirements.
Therefore the amplifier can apply more
power into the smaller frequency region.

WarningsWarnings

Warnings

WarningsWarnings

To prevent fire or shock hazard, do not
expose the MONOLITH IIIx CROSSOVER
to rain or moisture.

Hazardous voltage potentials exist in
this crossover. Do not operate with the
cover removed. There are no user
serviceable components inside. Refer
servicing to your authorized Martin­Logan dealer only.

Page12

PackagingPackaging

Packaging

PackagingPackaging

Please save all packaging and store in
a dry place away from potential fire
hazard. Your MONOLITH IIIx CROSSOVER
is a precision electronic instrument and
should be packaged properly in its
original carton any time shipment is
necessary. We hope that you will never

have occasion to return your unit to our
factory for service, but in the event that
servicing should prove necessary, or
other occasion requiring shipment
occurs, the original packaging will
protect your unit from unnecessary
damage or delay.

Monolith III User's Manual

AA

C PC P

A

C P

AA

C PC P

ower Connectionower Connection

ower Connection

ower Connectionower Connection

Plug in AC mains only after allPlug in AC mains only after all

Plug in AC mains only after all

Plug in AC mains only after allPlug in AC mains only after all
signal connections have beensignal connections have been

signal connections have been

signal connections have beensignal connections have been

made and you have verified thatmade and you have verified that

made and you have verified that

made and you have verified thatmade and you have verified that
both amplifiers are switched off.both amplifiers are switched off.

both amplifiers are switched off.

both amplifiers are switched off.both amplifiers are switched off.

We have provided your MONOLITH IIIx
CROSSOVER with the proper IEC
standard 3-conductor power cords with
3-prong grounding plug. This cord
should be firmly inserted into the AC
power receptacle located on the rear
panel of the crossover, then to any

Signal ConnectionSignal Connection

Signal Connection

Signal ConnectionSignal Connection

Insert your pre-amps' output cables into
the crossovers' INPUT jacks, then
connect your low-pass amplifiers' input
cables to the crossovers' LOW OUT­PUT jacks, and your high-pass amplifi­ers' input cables to the
HIGH OUTPUT jacks.

convenient AC wall outlet. For absolute
protection,

ground

grounding of the MONOLITH IIIx CROSS-
OVER chassis and will protect you from
electrical shock.

We do not recommend the replacement
or use of "deluxe" or "super" AC power
cords. Many of these designs eliminate
the ground prong of the male plug and
therefore do not follow IEC convention
standards. As such, they present the
possibility of shock hazard.

do not defeat the power plug

. This provides powerline

Your MONOLITH IIIx CROSSOVER has no
power switch as it has been designed
to remain on continuously and should
remain connected to a continuous AC
power source.

Your crossover is wired for the power
service supplied in the country of
original consumer sale unless manu­factured on special order. The AC
power rating applicable to a particular
unit is specified both on the packing
carton and on the serial number plate
attached to the crossover.

Plug in AC mains only after allPlug in AC mains only after all

Plug in AC mains only after all

Plug in AC mains only after allPlug in AC mains only after all
signal connections have beensignal connections have been

signal connections have been

signal connections have beensignal connections have been

made and you have verified thatmade and you have verified that

made and you have verified that

made and you have verified thatmade and you have verified that
both amplifiers are switched off.both amplifiers are switched off.

both amplifiers are switched off.

both amplifiers are switched off.both amplifiers are switched off.

Next, connect the speaker leads from
the high-pass amplifier to the HI
SIGNAL INPUTS on the back of the
MONOLITH III. Then connect the low­pass amplifier to the LO SIGNAL
INPUTS. Please refer to the pictorial
diagram,

Monolith III User's Manual

Figure 4 ,

at right.

Figure 4Figure 4

Figure 4:

Figure 4Figure 4

MONOLITH IIIx CROSSOVER

connection.

Page13

IIIx Operation

Crossover SettingsCrossover Settings

Crossover Settings

Crossover SettingsCrossover Settings

Before you do any formal listening,
you must set a pair of switches in the
crossover. However, if you are using
identical amplifiers (i.e. same make
and model) for the high and low-pass
sections of the Monolith, you may use
the factory settings and skip this step.

On the back panel of the crossover
there are two cut-outs that allow you
to access two red dip switches. These
switches adjust the low-pass gain so
that you may balance the gain
between the high-pass and low-pass
amplifiers if they have different gain
characteristics. We have even
enclosed a red "dip stick" tool to assist
you with this procedure.

The following formula will help you
calculate the relative gain of your
amplifiers:

Amplifier gain is defined as:

20 log20 log

20 log

20 log20 log

At right, in

(Rated Output @ 8 ohms) x 8(Rated Output @ 8 ohms) x 8

(Rated Output @ 8 ohms) x 8

(Rated Output @ 8 ohms) x 8(Rated Output @ 8 ohms) x 8
Input Sensitivity Input Sensitivity

Input Sensitivity

Input Sensitivity Input Sensitivity

Figure 5,

is a list of switch
settings to help you select the proper
gain switch settings.

As you detent the switch towards the
ONON

ON position, you are engaging that

ONON
switch. Each switch detent away from
position “4” either increases or
decreases the output of the low-pass
amplifier. In order to properly engage
a switch, you need to have all other
switches in the

OFF OFF

OFF position. If the

OFF OFF
high-pass and low- pass amplifiers are
identical or have the same gain, the
system is designed to operate with
both switches set to “4” (Position “4”
represents 0dB of gain).

optimal setting is to locate the
microphone of a spectrum analyzer in
the room near your seating position,
play pink noise through the system
and begin to observe the relationship
of the electrostatic transducer and the
subwoofer at the crossover point
which is 125 Hz. Your gain settings
will be correct when the display is flat
and consistent. You want the energy
below 100 Hz to be roughly compa­rable to the energy above 100 Hz. If
you now have reasonable tonal
balance from 60 Hz onward to 200
Hz, then you have the optimal
frequency balance at the crossover
point.

Keep in mind that specifications and
equipment can determine the best
place to begin, but your ears are the
most critical instruments available.
Listen to music and adjust for your
best personal balance.

ONON

ON

ONON

None

*1
*2

2&1

*3

3&1

*4
4&1
4&2

Figure 5Figure 5

Figure 5: Low-pass attenuation switch settings.

Figure 5Figure 5

NOTE: Start with "*" settings first, then fine

GAINGAIN

GAIN

GAINGAIN

-6.0 dB

-4.5 dB

-3.0 dB

-2.0 dB

-1.5 dB

-1.0 dB
0 dB

+0.5 dB
+1.0 dB

tune using the intermediate settings.

ONON

ON

ONON

*5
5&2
5&3

*6
6&3
6&5

*7
7&6

*8

Bass Contour ControlsBass Contour Controls

Bass Contour Controls

Bass Contour ControlsBass Contour Controls

You will notice that there are two
controls on the front of the MONOLITH
IIIx CROSSOVER. The left control is
labeled frequency and the right
control is labeled boost/cut. (See

Figure 6

.) These are a very accurate
and precise pair of controls that allow
you to adjust your speakers output in
the most problematic area of music
reproduction; the bass region.

Your Room and BassYour Room and Bass

Your Room and Bass

Your Room and BassYour Room and Bass

Today we are finding that all elements
in the audio chain can and will affect
your system's performance. Of these
elements, your room is the worst
offender. Once the precisely tailored
musical signal is launched from your
speaker system, your room then has

its way with that
musical signal;
particularly with the
larger wave-

GAINGAIN

GAIN

GAINGAIN

+1.5 dB
+2.0 dB
+2.5 dB
+3.0 dB
+3.5 dB
+4.0 dB
+4.5 dB
+5.0 dB
+6.0 dB

lengths of the
bass region. Your
room will enhance
and cancel certain
frequencies,
making a perfect
speaker look less
than perfect in the
best of instances
and like a jumbled
mess in the worst
of instances. The
front panel
controls of the
crossover can be
used much like an
accurate bass/

If equipped, the best way to obtain the

Page14

Monolith III User's Manual

room equalizer, designed to neutral­ize the specific problem areas of your
room, thus helping you optimize the
performance of the MONOLITH III.

Tuning Your RoomTuning Your Room

Tuning Your Room

Tuning Your RoomTuning Your Room

One of the best ways to assess how
your room is affecting your system's
performance is by doing a 1/3 octave
analysis of your room. These devices,
called 1/3 octave analyzers, may be
obtained or rented from your dealer.
Some dealers can even provide you
with this analysis. The information
gained by this analysis will help you
establish the proper control settings
for your MONOLITH IIIx CROSSOVER,

thus allowing you to bring your

system back to “flat” for optimal
system performance.

If a real-time analyzer is not available,
a simple sine-wave generator and
your ears may be used. By attaching
the sine-wave generator to your
system and slowly and consistently

sweeping from 100 Hz to 20 Hz and
back again, and listening in different
places in your room for what we call
room nodes, or depressions, you can
hear where the room either empha­sizes certain bass frequencies or
cancels them. If you set the frequency
control of the crossover to the same
frequency as that of the "worst
offender", and adjust the boost/cut
control to its appropriate position
(either up to cancel a void or down to
cancel a peak), you should begin to
establish a smooth progression from
lows to highs. Your goal here is to
have no lumps or recessions
throughout the low frequency sweep.

If neither a real-time analyzer nor a
sine-wave generator are available, put
on your favorite musical cut with
“moving bass” (bass information that
moves up and down the scale). Listen
carefully to this cut once or twice and
note whether the progression of bass
is smooth throughout the musical
spectrum. If it is smooth and extended
without any noticeable absences or

increases of music at each note, then
you have an optimal sound with no
need to adjust the crossover controls.
However, if you note an absence or
increase of energy at a specific area,
adjust your frequency control to that
frequency and boost or cut progres­sively depending on whether you want
more bass or less bass. Here,
experimentation will be the factor.
Inevitably, this is the final experiment.
Even after using a sine-wave genera­tor or real-time analyzer you will want
to listen and fine-tune your system
with real music using your ears.

Remember, what we often perceive
as deep bass actually occurs at 40 to
50 Hz. Energy below 30 Hz is virtually
inaudible. You may sense it and feel it
as pressurization and movement in
your body, but you don’t really hear it.
So, when you are experiencing bass
energy, you will probably want to set
your controls in the 30 to 50 Hz range
and adjust them accordingly.

35 Hz 45 Hz

30 Hz

Monolith III User's Manual

40 Hz

f r e q u e n c y

Figure 6Figure 6

Figure 6:

Figure 6Figure 6

50 Hz

MONOLITH IIIx CROSSOVER

-2dB

-4dB

b o o s t / c u t

Bass Contour controls.

0dB

+2dB

+4dB

Page15

IIIx Operation

IIIx Technical Description

Musical TastesMusical Tastes

Musical Tastes

Musical TastesMusical Tastes

An added benefit of the contour
controls on the IIIx CROSSOVER, is
the ability to adjust your speaker's
personality to your style of listening.

It is well known that an “audiophile”
listening priority is different from that of
“rock” or “classic European” listening
orientation. By setting your frequency
control to 30 Hz and the boost/cut
control to 0dB, you will have what is
known as the "Audiophile setting". This
setting allows the deepest bass
extension and most linear theoretic
performance. Experimenting slightly
with the boost/cut control will give you
either a drier or deeper and more
extended performance. However, if a
“rock” orientation is your preference,
set the frequency control between 40
to 50 Hz with a slight boost, and you
will get more of the emphasized
percussive effect of rock music. The
last priority, “classic European”,
consists of a dry, clean, very tight bass
structure. It can be accomplished by
resetting the frequency control to 30
Hz and turning down the boost/cut
control. At this point, you will still have
deep and extended bass, but it will be
slightly rolled off to give you a very tight,
defined performance level.

In the final evaluation, your ears will
determine where these controls
should be positioned. They have been
established for your flexibility and use
and can be used much like an accurate
bass/room equalizer. So don't be
afraid to experiment and have fun!

Theory of OperationTheory of Operation

Theory of Operation

Theory of OperationTheory of Operation

The audio signal coming from the pre­amplifier of your audio system is
typically representitive of a low imped­ance voltage source. There are a few
preamplifiers, such as older tube
designs, which may not conform to
this, as they have a much higher output
impedance. In addition many cables
can change the preamplifiers output
characteristics.

In order to assure a high level of
performance with all types of preamps
and cables, the MONOLITH IIIx CROSS-
OVER has a high input impedance, low
output impedance buffer for its first
stage. Futhermore, since there is no
substitute for isolation to prevent
various filter sections from interacting
with each other (normally the high
pass and low pass filters), the MONO-
LITH IIIx CROSSOVER has a separate
buffer for the high-pass and the low­pass audio path.

These buffers are designed using two
complimentary J-FET devices per
buffer, strapped in unity gain, voltage
follower topology. Two additional
bipolar devices are used as current
sources only, enabling the J-FETs to
be completely current biased. This
complimentary J-FET buffer is used
repeatedly throughout the crossover,
except for the output stage which
requires gain.

In being a dedicated electronic
crossover/equalizer, it is vital to tailor
the system to the needs of the
speaker. Planar speakers have two
main areas of concern: 1) Rear wave
cancellation, which causes a decrease
in the speaker’s output below 500 Hz,
and 2) Primary resonance, which is the
frequency the speaker is tuned to.

Rear wave cancellation requires
corrective equalization beginning at
500 Hz and increasing to roughly 12dB
at 100 Hz. Primary resonance affects
this response as well, because the
speaker is effectively out of control at
primary resonance. A notch filter works
well to negate the effects of this
typically 12dB resonance. The decision
of resonance tuning and rear wave
cancellation compensation, combined
in balance with the high frequency roll­off point, is a system decision based
on the sonic properties of the speaker
itself.

The MONOLITH IIIx CROSSOVER's high-
pass pathway utilizes three separate
filter sections; one for raising energy
between 100 Hz and 500 Hz, empha­sizing 100 Hz (referred to as a shelving
filter), another for decreasing energy at
the speaker resonance (notch filter)
and a third high-pass filter.

Page16

Monolith III User's Manual

The woofer has another set of require­ments based upon its inherent dis­placement limitations. In order to
recreate strong low frequency energy
using a dynamic cone drive, a high “Q”
driver in a large tuned (usually ported)
box is required. The trade-off with this
approach is poor speed, acceleration,
and damping of the woofer driver. The
superior performance of the electro-

static element demands that the woofer
be a fast, quick-to-change, well damped
driver so that it will blend with the
electrostatic transducers characteristics
properly. This is best obtained by using
a low “Q”, low mass, small box design.
However, to maintain good low fre­quency response with this approach,
low frequency boost is required. Here,
again, a shelving filter is used.

To prevent subsonic energy from taxing
the listener, room, and driver, a sub­sonic high-pass filter is necessary. A
third filter is reserved for low-pass filter
operation. The characteristics of
frequency and “Q” of each filter is
affected by component value selection
within each filter section.

Figure 7Figure 7

Figure 7:

Figure 7Figure 7

Monolith III User's Manual

MONOLITH IIIx CROSSOVER

block diagram of circuit.

Page17

Room Acoustics

Your RoomYour Room

Your Room

Your RoomYour Room

This is one of those areas that requires
a little background to understand and
some time and experimentation to
obtain the best performance from your
system.

Your room is actually a component and
an important part of your system. This
component is a very large variable and
can dramatically add to, or subtract
from, a great musical experience,
depending on how well you attend to it.

All sound is composed of waves. Each
note has its own wave size, with the
lower bass notes literally encompass­ing from 10' to as much as 40'! Your
room participates in this wave experi­ence like a 3 dimensional pool with
waves reflecting and becoming
enhanced depending on the size of the
room and the types of surfaces in the
room.

Remember, your audio system can
literally generate all of the information
required to recreate a musical event in
time, space, and tonal balance. The
purpose of your room, ideally, is to not
contribute to that information. However,
every room does contribute to the
sound and the better speaker manufac­turers have designed their systems to
accommodate this phenomenon.

TerminologyTerminology

Terminology

TerminologyTerminology

Standing WavesStanding Waves

Standing Waves. The parallel walls in your room will reinforce certain notes to

Standing WavesStanding Waves

the point that they will sound louder than the rest of the audio spectrum
and cause “one note bass”, “boomy bass”, or “tubby bass”. For instance,
100Hz represents a 10' wavelength. Your room will reinforce that specific
frequency if one of the dominant dimensions is 10'. Large objects in the
room such as cabinetry or furniture can help to minimize this potential
problem. Some serious “audiophiles” will literally build a special room
with no parallel walls just to get away from this phenomenon.

Reflective SurfacesReflective Surfaces

Reflective Surfaces. The hard surfaces of your room, particularly if close to

Reflective SurfacesReflective Surfaces

your speaker system, will reflect those waves back into the room over and
over again, confusing the clarity and imaging of your system. The smaller
sound waves are mostly affected here and occur in the mid and high
frequencies. This is where voice and frequencies as high as the cymbals
can occur.

Near Field ReflectionsNear Field Reflections

Near Field Reflections. Those reflective surfaces of the room that are the

Near Field ReflectionsNear Field Reflections

closest to your speaker system, particularly if they are hard surfaces, can
reflect the musical energy back into the room, confusing the imaging and
tonal balance of your system. Excessive brightness can result from this
condition and diffuse, ill defined imaging can easily occur if too many
surfaces near your speakers are hard and sharp in their relative angle to
your system.

Resonant Surfaces and ObjectsResonant Surfaces and Objects

Resonant Surfaces and Objects. All of the surfaces and objects in your room

Resonant Surfaces and ObjectsResonant Surfaces and Objects

are subject to the frequencies generated by your system. Much like an
instrument, they will vibrate and “carry on” in syncopation with the music
and contribute in a negative way to the music. Ringing, boominess, and
even brightness can occur simply because they are “singing along” with
your music.

Resonant CavitiesResonant Cavities

Resonant Cavities. Small alcoves or closet type areas in your room can be

Resonant CavitiesResonant Cavities

chambers that create their own “standing waves” and can drum their own
“one note” sounds.

Let’s talk about a few important terms
before we begin.

Page18

Clap your hands. Can you hear an instant echo respond back ? You’ve
got near-field reflections. Stomp your foot on the floor. Can you hear a
“boom”? You’ve got standing waves or large panel resonances such as a
poorly supported wall. Put your head in a small cavity area and talk loudly.
Can you hear a booming? You’ve just experienced a cavity resonance.

Monolith III User's Manual

Rules of ThumbRules of Thumb

Rules of Thumb

Rules of ThumbRules of Thumb

Hard vs. Soft SurfacesHard vs. Soft Surfaces

Hard vs. Soft Surfaces. If one surface of your

Hard vs. Soft SurfacesHard vs. Soft Surfaces

room (wall, floor, ceiling) is hard, a good
rule of thumb suggests to try to have the
opposing surface soft. So, if you have a
hard wall of glass or paneling on one side
of the room, it is best to have drapery or wall
hangings on the opposing wall. If you have
a hard ceiling, it generally is a good idea to
have a soft floor of carpeting or area rugs.
Large, soft furniture also counts to help
damp a highly reflective room.

This rule suggests that a little reflection is
good. As a matter of fact, some rooms can
be so “over damped” with carpeting, drapes
and sound absorbers that the music
system can sound dull and lifeless. On the
other hand, rooms can be so hard that the
system can sound like a gymnasium with
too much reflection and brightness. The
point is that balance is the optimum
environment.

Break-up ObjectsBreak-up Objects

Break-up Objects. Objects with complex

Break-up ObjectsBreak-up Objects

shapes, such as bookshelves, cabinetry,
and multiple shaped walls can help to
break up those sonic gremlins and diffuse
any dominant frequencies.

Solid CouplingSolid Coupling

Solid Coupling. Your loudspeaker system

Solid CouplingSolid Coupling

generates frequency vibrations or waves
into the room. This is how it creates sound.
Those vibrations will vary from 20 per
second to 20,000 per second. If your
speaker system is not securely planted on
the floor or solid surface, it can shake as it
produces sound, and consequently the
sound can be compromised. If your
speaker is setting on the carpet and only
foot gliders are used, the bass can be ill
defined and even boomy. Additionally, the
imaging can be poorly located and diffuse if
the system is not on solid footing.

Bipolar Speakers and Your RoomBipolar Speakers and Your Room

Bipolar Speakers and Your Room

Bipolar Speakers and Your RoomBipolar Speakers and Your Room

Martin-Logan electrostatic loudspeakers are known as bipolar radiators.
This means that they produce sound from both their fronts and their
backs. Consequently, musical information is reflected by the wall behind
them and may arrive either in or out of step with the information produced
by the front of the speaker.

The low frequencies can either be enhanced or nulled by the position from
the back wall. Your Monoliths have been designed to be placed 2 to 3 feet
from the back wall to obtain the best results, however your room may see
things differently. So, listening to the difference of the bass response as a
result of the changes in distance from the back wall can allow you to get
the best combination of depth of bass and tonal balance.

The mid-range and high frequencies can also be affected, but in a
different way. The timing of the first wave as it is first radiated to your ears
and then the reflected information as it arrives at your ears later in time,
can result in confusion of the precious timing information that carries the
clues to imaging and, consequently result in blurred imaging and exces­sive brightness. Soft walls, curtains, wall hangings, or sound dampeners
(your dealer can give you good information here) can be effective if these
negative conditions occur.

Vertical DispersionVertical Dispersion

Vertical Dispersion

Vertical DispersionVertical Dispersion

As you can see from the illustrations, your Monolith III speakers project a
controlled dipersion pattern. Each Monolith is a four foot line source
beginning two feet above floor level. This vertical dispersion profile
minimizes interactions with the floor and the ceiling.

Horizontal DispersionHorizontal Dispersion

Horizontal Dispersion

Horizontal DispersionHorizontal Dispersion

Your Monoliths launch a 30 degree dispersion pattern when viewed from
above. This horizontal dispersion field gives you a choice of good seats for
the performance while minimizing interactions with side walls.

Make sure both speakers stand exactly at the same vertical angle,
otherwise the image can be skewed or poorly defined. The wave launch of
both speakers is extremely accurate in both the time and spectral domain
and, consequently small refined adjustments can result in noticeable
sonic improvements.

Monolith III User's Manual

Page19

Room Acoustics

Dispersion ConceptsDispersion Concepts

Dispersion Concepts

Dispersion ConceptsDispersion Concepts

In the field of loudspeaker design, it is
common knowledge that as the wave
becomes progressively smaller than the
transducer producing it, the dispersion
of that wave becomes more and more
narrow, or directional. This occurs as
long as the transducer is a flat surface.

Historically, most attempts to achieve
smooth dispersion from large flat panel
transducers resulted in trade-offs. After
exhaustive testing of these different
solution attempts, we found an ele­gantly simple, yet very difficult to execute
solution. By curving the radiating

As can be seen, point source concepts
invite a great deal of room interaction.
While delivering good frequency re­sponse to a large listening audience,
imaging is consequently confused and
blurred.

Even though they suffer from "venetian
blind" effect, angled multiple panel
speakers can deliver good imaging,
but only to specific spots in the listen­ing area.

surface, we create the effect of a
horizontal arc. This allows the engi­neers at Martin-Logan to control the
high frequency dispersion pattern of our
transducers. That is why you see the
gentle curve on our products.

Page20

A controlled 30-degree cylindrical
wave-front, which is a
exclusiveexclusive

exclusive, offers optimal sound distri-

exclusiveexclusive
bution with minimal room interaction.
The result is solid imaging with a wide
listening area.

Martin-LoganMartin-Logan

Martin-Logan

Martin-LoganMartin-Logan

Monolith III User's Manual

Placement

General PlacementGeneral Placement

General Placement

General PlacementGeneral Placement

Start by making certain that both speakers are the same
distance from the walls behind or beside them and that their
“toe-in” angle is the same. At this time you may want to enlist
the help of a friend or family member to assist you.

It is generally true that, as you move your speakers farther
forward into the listening environment, you will derive more
spaciousness from them. Toeing them toward the middle of
the listening area will enhance brightness.

As you place and listen, keep in mind that tight bass and
clear resolution indicate proper placement and that the
acoustical image is in focus. Don’t hesitate to experiment,
but give each new combination of positions a thorough test.
The time and effort you invest here will be well spent.

By now your speakers should be placed approximately 2 to 3
feet from the back wall and at least 1 to 2 feet from the side
walls. Your sitting distance should be further than the
distance between the speakers themselves. What you are
trying to attain is the impression of good center imaging and
stage width.

There is no exact distance between speakers and listener,
but there is a relationship. In long rooms, naturally, that
relationship changes. The distance between the speakers
will be far less than the distance from you to the speaker
system. However, in a wide room you will still find that if the
distance from the listener to the speakers becomes smaller
than the distance between the speakers themselves, the
image will no longer focus in the center.

The Back WallThe Back Wall

The Back Wall

The Back WallThe Back Wall

Near-field reflections can also occur from your back wall. If
your listening position is close to a back wall, these reflec­tions can cause problems and confuse the quality of
imaging. Actually it is better for the back wall to be soft than to
be bright. If you have a hard back wall and your listening
position is close to it, experiment with devices that will soften
and absorb information, ie: wall hangings and possibly even
sound absorbing panels.

The Front WallThe Front Wall

The Front Wall

The Front WallThe Front Wall

The wall behind your speakers should not be extremely hard
or soft. For instance, a pane of glass will cause reflections,
brightness, and confused imaging. Curtains, drapery, and
objects such as bookshelving can be placed along the back
wall to tame an extremely hard surface. A standard sheet
rock or textured wall is generally an adequate back surface if
the rest of the room is not too bright and hard.

Sometimes walls can be too soft. If the entire front wall
consists of only heavy drapery, your system can literally
sound too soft or dull. You will hear dull, muted music with
little ambience. Harder room surfaces will actually help in
this case.

The front surface should, optimally, be one long wall without
any doors or openings. If you have openings, the reflection
and bass characteristics from one channel to the other can
be different.

Now that you have positioned your speaker system, spend
some time listening. Wait to make any major changes in
your initial set-up for the next few days as the speaker
system itself will change subtly in its sound. Over the first 20
hours of play the actual tonal quality will change slightly with
deeper bass and more spacious highs resulting.

After a few days of listening you can begin to make refine­ments and hear the differences of those refinements.

Monolith III User's Manual

The Side WallsThe Side Walls

The Side Walls

The Side WallsThe Side Walls

The same requirements exist for side walls. Additionally, a
good rule of thumb is to have the side walls as far away from
the speaker sides as possible, minimizing near field side
wall reflections. Sometimes, if the system is bright or the
imaging is not to your liking, and the sidewalls are very near,
try putting curtains or softening material directly to the edge
of each speaker. An ideal side wall, however, is no side wall
at all.

Page21

Placement

ExperimentationExperimentation

Experimentation

ExperimentationExperimentation

Toe-inToe-in

Toe-in.

Toe-inToe-in

Now you can begin to experiment.
First begin by toeing your speakers
in towards the listening area and
then toeing them out. You will
notice that the tonal balance
changes ever so slightly. You will
also notice the imaging changing
ever so slightly. Generally it is found
that the ideal listening position is
with the speakers slightly toed-in
so that you are listening to the inner
third of the curved transducer
section.

Experimenting with the toe-in will
help in terms of tonal balance. You
will notice that as the speakers are
toed-out, the system becomes
slightly brighter than when toed-in.
This design gives you the flexibility
to modify a soft or bright room.

Tilting the Speakers.Tilting the Speakers.

Tilting the Speakers.

Tilting the Speakers.Tilting the Speakers.

(Backwards and Forwards)

As can be seen from the diagrams
in the Room Acoustics section of
this manual, the vertical dispersion
is directional above and below the
stat panel itself. If you sit in a tall

chair, you may get better perform­ance by tilting the speakers back
so that the high frequencies are on
axis with your ears. Otherwise, with
a normal sofa and normal listen­ing, tilt the speakers only slightly
back if not straight up. Make sure,
when listening, that the vertical
alignment, distance from the back
wall, and toe in is exactly the same
from one speaker to the other. This
will greatly enhance the quality of
your imaging.

Imaging.Imaging.

Imaging.

Imaging.Imaging.

In their final location, your Monoliths
should have a stage width some­what wider than the speakers
themselves. On well recorded
music, the instruments should
extend beyond the edges of each
speaker to the left and to the right,
yet a vocalist should appear directly
in the middle. The size of the
instruments should be neither too
large nor too small. Additionally,
you should find good clues as to
stage depth.

Bass Response.Bass Response.

Bass Response.

Bass Response.Bass Response.

Your bass response should neither
be one note nor should it be too
heavy. It should extend fairly deep
to all but the deepest organ
passages yet it should be tight and
well defined. Kick-drums should be
tight and percussive, string bass
notes should be uniform and
consistent throughout the entirety of
the run without any booming or
thudding.

Tonal Balance.Tonal Balance.

Tonal Balance.

Tonal Balance.Tonal Balance.

Voices should be natural and full,
cymbals should be detailed and
articulate yet not bright and
piercing, pianos should have a nice
transient characteristic and deep
tonal registers as well. If you
cannot attain these virtues, re-read
the section on Room Acoustics.
This will give you clues on how to
get closer to those ideal virtues.

A Final WordA Final Word

A Final Word

A Final WordA Final Word

Final Placement.Final Placement.

Final Placement.

Final Placement.Final Placement.

After obtaining good wall treat­ments and attaining proper angle,
begin to experiment with the
distance from the back wall. Move
your speaker slightly forward into
the room. What happened to the
bass response? What happened to
the imaging? If the imaging is more
open and spacious and the bass
response tightened, that is a
superior position. Move the
speakers back six inches from the
initial set-up position. Again, listen
to the imaging and bass response.
There will be a position where you
will have pin-point imaging and
good bass response. That position
becomes the point of the optimal
placement from the back wall.

Now experiment with placing the
speakers farther apart. As the
speakers are positioned farther
apart, listen again, not so much for
bass response but for stage width
and good pin-point focusing.

Your ideal listening position and
speaker position will be deter­mined by the following:

1. Tightness and extension of
bass response.

2. The width of the stage.

3. The pin-point focusing of
imaging.

Once you have found the best of all
three of those considerations, you
will have your best speaker
location.

Page22

Monolith III User's Manual

General Information

Associated EquipmentAssociated Equipment

Associated Equipment

Associated EquipmentAssociated Equipment

Your Martin-Logan Dealer was
carefully selected by our company
because they are knowledgeable,
experienced and dedicated to musical
excellence and customer satisfaction.

They have the ability to help you
acquire the very best in audio equip­ment. They are likely to choose that
equipment from among a small group
of manufacturers that are committed to
the faithful recreation of music.

Your new MONOLITH III speakers are
quite honest in revealing the relative
strengths and weaknesses of the
equipment used with them. While the
Monolith will bring to life the sonic
delights of state-of-the-art compo­nents, it will with equal clarity bring out
any system flaws. This does not mean
that expensive equipment is a
prerequisite to good sound from the
Monolith, but rather that the equipment
must be wisely selected and setup
with care. The rewards will be well
worth the effort.

As time goes by, you may find it
instructive to discuss with your dealer
the merits and advantages of carefully
upgrading certain pieces of your
associated equipment.

CareCare

Care

CareCare

The Martin-Logan Monolith has been
carefully designed and precisely
engineered. With a little care you can
rest assured that they will continue to
look as good as they sound for years
to come.

Do not spray any cleaning solutions on
the electrostatic element, as this could
impair the speakers performance.
Dust may be removed with a brush
attachment on a vacuum cleaner or
you may blow it off with compressed
air. Silicone dusting sprays, abrasive

notnot

or solvent-based cleaners should
be used on any portions of the
speaker.

Solid FootingSolid Footing

Solid Footing

Solid FootingSolid Footing

It is best to have a the Monoliths
coupled firmly with the floor. After living
and experimenting with the placement
of your Monoliths, you should use the
spikes included in your owners kit.
Bass response will tighten and
imaging will become more coherent,
fixed and detailed. It is best not to
implement the spikes however, until
you have decided upon the final
placement of the speaker, as they can
damage the floor if the speaker is
moved.

not

notnot

Enjoy YourselfEnjoy Yourself

Enjoy Yourself

Enjoy YourselfEnjoy Yourself

The MONOLITH III is a very refined
speaker and, as such, benefits from
careful set-up. With the information in
this manual in mind, you will find, over
your months of listening, that small
changes can result in demonstrable
differences. As you live with your
speakers, do not be afraid to experi­ment with their positioning until you
find the optimal relationship between
your room and your speaker system.
Your efforts will be rewarded.

You are now armed with the basics of
room acoustics and the specific
fundamentals of the MONOLITH III
loudspeaker system. Enjoy yourself
and happy listening.

Monolith III User's Manual

Page23

The Electrostatic Concept

How is it that music can be recreated by
something that you are able to see
through? Electrostatic energy makes
this possible.

Where the world of traditional loud­speaker technology deals with cones,
domes, diaphrams, and ribbons that
are moved with magnetism, the world
of electrostatic loudspeakers deals with
charged electrons attracting and
repelling each other.

To fully understand the electro­static concept , some back­ground information will be
helpful. Remember when you
learned, in a science or physics
class back in high school, that
like charges repel each other
and that opposite charges attract
each other? Well, this principle is
the foundation of the electrostatic
concept.

An electrostatic transducer
consists of three pieces: the
stators, the diaphragm and the
spacers. (See

Figure 8

.) The

diaphragm is what actually moves to
excite the air and create music. The
stator's job is to remain stationary,
hence the word stator, to provide a
reference point for the moving dia­phragm. The spacers provide the
diaphragm with a fixed distance in
which to move between the stators.

As your amplifier sends music signals
to an electrostatic speaker, these

An Electrostatic TransducerAn Electrostatic Transducer

An Electrostatic Transducer

An Electrostatic TransducerAn Electrostatic Transducer

Diaphragm

Spacer

signals are changed into two high­voltage signals that are equal in
strength but opposite in polarity. These
high-voltage signals are then applied to
the stators. The resulting electrostatic
field, created by the opposing high
voltage on the stators, works simultane­ously with and against the diaphragm,
consequently moving it back and forth,
producing music. This technique is
known as push-pull operation and is a

Stator

Page24

Figure 8Figure 8

Figure 8. Cut away view of an electrostatic transducer.

Figure 8Figure 8

Notice the simplicity due to minimal parts usage.

Monolith III User's Manual

major contributor to the sonic purity of
the electrostatic concept due to its
exceptional linearity and low distortion.

Since the diaphragm of an electrostatic
speaker is uniformly driven over its
entire area, it can be extremely light and
flexible. This allows it to be very
responsive to transients, thus perfectly
tracing the music signal. As a result ,
great delicacy, nuance and clarity is

An Electromagnetic TransducerAn Electromagnetic Transducer

An Electromagnetic Transducer

An Electromagnetic TransducerAn Electromagnetic Transducer

ConeSurround

Basket Assembly

Magnet

Voice Coil Magnetic Gap

possible. When you look at the prob­lems of traditional electromagnetic
drivers, you can easily see why this is
so beneficial .

The cones and domes which are used
in traditional electromagnetic drivers
cannot be driven uniformly because of
their design. Cones are driven only at
the apex. Domes are driven at their
perimeter. As a result, the rest of the

Dust Cap

Voice Coil Former

Spider (Suspension)

Magnet Assembly

cone or dome is just "along for the ride".
The basic concept of these drivers
require that the cone or dome be
perfectly rigid, damped and close to
massless. Unfortunately these condi­tions are not available in our world
today.

To make these cones and domes
move, all electromagnetic drivers must
use voice coils wound on formers,

spider assemblies, and
surrounds to keep the cone or
dome in position (see

9

.). These pieces, when

Figure

combined with the high mass of
the cone or dome materials
used, make it an extremely
complex unit with many weak­nesses and potential for failure.
These faults contribute to the
high distortion products found in
this type of driver and is a
tremendous disadvantage
when you are trying to change
motion as quickly and as
accurately as a loudspeaker
must (40,000 times per
second!).

Figure 9.Figure 9.

Figure 9. Cut away view of a typical moving coil driver.

Figure 9.Figure 9.

Notice the complexity due to the high number of parts.

Monolith III User's Manual

Page25

Martin-Logan Exclusives

1. Full Range Operation1. Full Range Operation

1. Full Range Operation

1. Full Range Operation1. Full Range Operation

The most significant advantage of
Martin-Logan's exclusive transducer
technology reveals itself when you look
at examples of other loudspeaker
products on the market today.

The MONOLITH III uses no crossover
networks above 125 Hz because they are
not needed. The MONOLITH III consists
of a single, seamless electrostatic
membrane reproducing all frequencies
above 125 Hz simultane­ously. How is this possible?

First we must understand that
music is not composed of
separate high, mid and low
frequency pieces. In fact, music
is comprised of a single complex
waveform with all frequencies
interacting simultaneously.

The electrostatic transducer
of the Monolith essentially
acts as an exact opposite of
the microphones used to
record the original event. A
microphone, which is a
single working element,
transforms acoustic energy
into an electrical signal that
can be amplified or pre­served by some type of
storage media. The MONO-
LITH III's electrostatic trans­ducer transforms electrical
energy from your amplifier
into acoustical energy.
Due to the limitations of
electromagnetic drivers, no
single unit can reproduce the

full range of frequencies. Instead, these
drivers must be designed to operate
within narrow, fixed bandwidths of the
frequency range and then combined
electrically so that the sum of the parts
equals the total signal. While nice in
theory, we must deal with real-world
conditions.

In order to use multiple drivers, a
crossover network is enlisted to attempt

Conventional Loudspeaker

TweeterTweeter

Tweeter

TweeterTweeter

Critical ZoneCritical Zone

Critical Zone

Critical ZoneCritical Zone

250 - 20kHz250 - 20kHz

250 - 20kHz

MidrangeMidrange

Midrange

MidrangeMidrange

WooferWoofer

Woofer

WooferWoofer

Martin-Logan MONOLITH III

MONOLITH IIIMONOLITH III

MONOLITH III

MONOLITH IIIMONOLITH III

ElectrostaticElectrostatic

Electrostatic

ElectrostaticElectrostatic

TransducerTransducer

Transducer

TransducerTransducer

WooferWoofer

Woofer

WooferWoofer

Figure 10. Figure 10.

Figure 10. Illustrates how a conventional speaker system

Figure 10. Figure 10.

must use a crossover network that has negative affects

on the musical performance unlike the

needs no crossover networks in the "critical zone".

250 - 20kHz250 - 20kHz

Critical ZoneCritical Zone

Critical Zone

Critical ZoneCritical Zone

250 - 20kHz250 - 20kHz

250 - 20kHz

250 - 20kHz250 - 20kHz

MONOLITH III MONOLITH III

MONOLITH III

MONOLITH III MONOLITH III

which

a division of the complex musical signal
into the separate pieces (usually highs,
mids, and lows) that each specific
driver was designed to handle. Unfortu­nately, due to the phase relationships
that occur within all crossover networks
and during the acoustical recombina­tion process, nonlinearities and severe
degradation of the music signal takes
place in the ear's most "critical zone".
See

Figure 10

.

The MONOLITH III's electro­static transducer can single­handedly reproduce all
frequencies above 100 Hz
simultaneously. So, you
have, in one transducer, the
ability to handle, in elegant
simplicity, the critical
frequencies above 100 Hz.

The crossover phase
discontinuities that are
associated with traditional
tweeter, midrange, and
woofer systems are elimi­nated. This results in a
dramatic improvement in
imaging and staging
performance due to the
minutely accurate phase
relationship of the full-range
panel wave launch.

Page26

Monolith III User's Manual

2. Curvilinear Line2. Curvilinear Line

2. Curvilinear Line

2. Curvilinear Line2. Curvilinear Line
Source Source

Source

Source Source

Since the beginning of Audio, achieving
smooth dispersion has long been a
problem for all loudspeaker designers.
Large panel transducers present even
more of a challenge because the larger
the panel, the more directional the
dispersion pattern becomes.

Full range electrostats have long been
one of the most problematic transduc­ers because they attain their full range
capabilities via a large surface area. It
looked as if they were in direct conflict to
smooth dispersion and almost every
attempt to correct this resulted in either
poor dispersion or a serious compro­mise in sound quality.

After extensive research, Martin-Logan
engineers discovered an elegantly
simple solution to achieve a smooth
pattern of dispersion without degrading
sound quality. By curving the horizontal
plane of the electrostatic transducer, a
controlled horizontal dispersion pattern
could be achieved, yet the purity of the
almost massless electrostatic dia­phragm remained uncompromised.
After creating this technology, we
developed the production capability to
bring this technology out of the labora­tory and into the market place.

You will find this proprietary Martin­Logan technology used in all of our
products. It is one of the many reasons
behind our reputation for high quality
sound with practical usability. This is
also why you see the unique "see
through" cylindrical shape of all Martin­Logan products.

3. Hybrid Technology3. Hybrid Technology

3. Hybrid Technology

3. Hybrid Technology3. Hybrid Technology

When Martin-Logan introduced the
Monolith back in 1982, it was the first
company to commercially recognize the
performance potential available by
mating the air-moving capabilities of a
dynamic woofer with the inherent speed
and accuracy of an electrostatic panel.

Since then, refinements in the actual
driver assemblies, crossover compo­nents, and materials used in the
construction of our hybrid speakers have
brought this concept to its full potential.

4. Vapor Deposited4. Vapor Deposited

4. Vapor Deposited

4. Vapor Deposited4. Vapor Deposited
FilmFilm

Film

FilmFilm

The diaphragm material used in all
Martin-Logan speakers employs an
extremely sophisticated conductive
surface that has been vapor deposited
on the polymer surface at an atomic
level. Copper oxide and palladium have
been vaporized and electrostatically
driven into the surface of the polymer
film in a vacuum chamber. This process
allows an optically transparent surface
adding no mass to the diaphragm that
is extremely uniform in its surface
resistivity characteristics. This uniform
surface resistivity controls the electro­static charge on the diaphragm surface
and regulates its migration. As a result,
no discharging or “arcing” can occur.

5. Transducer Integrity5. Transducer Integrity

5. Transducer Integrity

5. Transducer Integrity5. Transducer Integrity

All Martin-Logan transducers begin with
two pieces of high grade, cold rolled
steel. The rear stator is manufactured
from 16 gauge material while the front
stator from 18 gauge. These steel
pieces are then custom perforated and
insulated with an exotic nylon compos­ite coating. This proprietary coating
insulates the stator to 3 times its actual
needed working voltage and gives the
Monolith a wide margin of safe opera­tion. In addition to the electrical insula­tion properties, this coating also
provides the Monolith with a durable,
attractive finish that dampens the steel
to prevent ringing. These pieces are
then sandwiched with our exclusive
vapor deposited diaphragm and
spacers into a curved geometry and
bonded together with aerospace
adhesives whose strength exceeds that
of welding.

When all of these various techniques
are combined, we get a transducer that
is attractive, durable, highly rigid, well
dampened, and neutral.

Monolith III User's Manual

Page27

Questions

Could my children, pets, or myselfCould my children, pets, or myself

Could my children, pets, or myself

Could my children, pets, or myselfCould my children, pets, or myself
be shocked by the high-voltagebe shocked by the high-voltage

be shocked by the high-voltage

be shocked by the high-voltagebe shocked by the high-voltage
present in the electrostatic panel?present in the electrostatic panel?

present in the electrostatic panel?

present in the electrostatic panel?present in the electrostatic panel?

No. High voltage with low current is
not dangerous. As a matter of fact, the
high-voltage present in our speakers
is10 times less than the static
electricity that you generate when you
take off a sweater. (About 30,000
volts!)

What size of an amplifier should IWhat size of an amplifier should I

What size of an amplifier should I

What size of an amplifier should IWhat size of an amplifier should I
use with the Monoliths?use with the Monoliths?

use with the Monoliths?

use with the Monoliths?use with the Monoliths?

We recommend an amplifier with 100
to 200 watts per channel for most
applications.

Do I need an amplifier with highDo I need an amplifier with high

Do I need an amplifier with high

Do I need an amplifier with highDo I need an amplifier with high
current capability?current capability?

current capability?

current capability?current capability?

No. The Monolith's impedance
characteristics do not require that a
high current amplifier be used.
However, it is important that the
amplifier be stable operating into
varying impedance loads.

Should I unplug my Monoliths duringShould I unplug my Monoliths during

Should I unplug my Monoliths during

Should I unplug my Monoliths duringShould I unplug my Monoliths during
a thunderstorm?a thunderstorm?

a thunderstorm?

a thunderstorm?a thunderstorm?

Yes. Or before. It’s a good idea to
disconnect all of your audio/video
components during stormy weather.

Will my electric bill go ‘sky high’ byWill my electric bill go ‘sky high’ by

Will my electric bill go ‘sky high’ by

Will my electric bill go ‘sky high’ byWill my electric bill go ‘sky high’ by
leaving my speakers plugged in allleaving my speakers plugged in all

leaving my speakers plugged in all

leaving my speakers plugged in allleaving my speakers plugged in all
the time?the time?

the time?

the time?the time?

No. A pair of Monoliths draw about 5
watts maximum.

Is there likely to be any interactionIs there likely to be any interaction

Is there likely to be any interaction

Is there likely to be any interactionIs there likely to be any interaction
between the Monoliths and thebetween the Monoliths and the

between the Monoliths and the

between the Monoliths and thebetween the Monoliths and the
television in my Audio/Videotelevision in my Audio/Video

television in my Audio/Video

television in my Audio/Videotelevision in my Audio/Video
system?system?

system?

system?system?

Actually, there is less interaction
between a television and an electro­static speaker than between a
television and a conventional system.
The magnets in conventional speak­ers do interact with televisions tubes.
However, we do recommend that you
keep your speakers at least one foot
away from the television because of
the dynamic woofer they employ.

Will excessive smoke or dust causeWill excessive smoke or dust cause

Will excessive smoke or dust cause

Will excessive smoke or dust causeWill excessive smoke or dust cause
any problems?any problems?

any problems?

any problems?any problems?

Exposure to excessive smoke or dust
may potentially affect the performance
of the electrostatic membrane. When
not in use, you should unplug the
speaker and cover with the plastic
bags that the speakers were originally
packed in.

If my child punctured the diaphragmIf my child punctured the diaphragm

If my child punctured the diaphragm

If my child punctured the diaphragmIf my child punctured the diaphragm
with a pencil, stick, or similar item.,with a pencil, stick, or similar item.,

with a pencil, stick, or similar item.,

with a pencil, stick, or similar item.,with a pencil, stick, or similar item.,
how extensive would the damage tohow extensive would the damage to

how extensive would the damage to

how extensive would the damage tohow extensive would the damage to
the speaker be?the speaker be?

the speaker be?

the speaker be?the speaker be?

You should probably replace the
electrostatic element. However, this
depends upon the extent of the
damage.

Will exposure to sunlight affect theWill exposure to sunlight affect the

Will exposure to sunlight affect the

Will exposure to sunlight affect theWill exposure to sunlight affect the
life or performance of the Monolith?life or performance of the Monolith?

life or performance of the Monolith?

life or performance of the Monolith?life or performance of the Monolith?

We recommend that you not place
your Monoliths in direct sunlight as
the ultraviolet (UV) rays from the sun
can cause deterioration of the
electrostatic membrane. However,
small exposures to UV should not
cause a problem.

Page28

Monolith III User's Manual

Troubleshooting

No Output.No Output.

No Output.

No Output.No Output.

Check that all your system components are turned on.

Check your speaker wires and connections.

Check all interconnecting cables.

Weak Output, Loss of Highs.Weak Output, Loss of Highs.

Weak Output, Loss of Highs.

Weak Output, Loss of Highs.Weak Output, Loss of Highs.

Check the power cord. Is it properly connected to the
speaker?

If you are bi-amplifiying, check your high frequency
amplifier. Is it functioning properly?

Exaggerated Highs, Brightness.Exaggerated Highs, Brightness.

Exaggerated Highs, Brightness.

Exaggerated Highs, Brightness.Exaggerated Highs, Brightness.

Check the toe-in of the speakers. Read Room Place-
ment for more information.

Muddy BassMuddy Bass

Muddy Bass

Muddy BassMuddy Bass

Check placement. Try moving the speakers closer to
the back and side walls.

Check the type of feet being used. Try attaching the
coupling spikes.

If you are using the IIIx CROSSOVER, adjust the bass
contour controls until you get the desired response

Lack of BassLack of Bass

Lack of Bass

Lack of BassLack of Bass

Check your speaker wires. Is the polarity correct?

Poor ImagingPoor Imaging

Poor Imaging

Poor ImagingPoor Imaging

Check placement. Are both speakers the same dis­tance from the walls? Do they have the same amount
of toe-in? Try moving the speakers away from the back
and side walls.

Check the polarity of the speaker wires. Are they
connected properly?

Popping and Ticking Sounds, Funny NoisesPopping and Ticking Sounds, Funny Noises

Popping and Ticking Sounds, Funny Noises

Popping and Ticking Sounds, Funny NoisesPopping and Ticking Sounds, Funny Noises

These occasional noises are harmless and will nut hurt
your audio system or your speakers. All electrostatic
speakers are guilty of making odd noises at one time or
another.

These noises may be caused by dirt and dust particles
collecting on the speaker, by high humidity or by AC line
fluctuations that may occur in your area.

Dirt and dust may be vacuumed off with a brush
attachment connected to your vacuum cleaner or you
may blow them off with compressed air.

DO NOT SPRAY ANY KIND OF CLEANING AGENT
ON OR IN CLOSE PROXIMITY TO THEM.

Monolith III User's Manual

Page29

Glossary

ACAC

AC. Abbreviation for alternating

ACAC

current.

Active crossoverActive crossover

Active crossover. Uses active

Active crossoverActive crossover

devices (transistors, IC’s,
tubes) and some form of power
supply to operate.

AmplitudeAmplitude

Amplitude. The extreme range of a

AmplitudeAmplitude

signal. Usually measured from
the average to the extreme.

ArcArc

Arc. The visible sparks generated by

ArcArc

an electrical discharge.

BandwidthBandwidth

Bandwidth. The range of frequencies

BandwidthBandwidth

within a radiation band required
to transmit a particular signal.

BassBass

Bass. The lowest frequencies of

BassBass

sound.

Bi-AmplificationBi-Amplification

Bi-Amplification. Uses an electronic

Bi-AmplificationBi-Amplification

crossover or line-level passive
crossover and separate power
amplifiers for the high and low
frequency loudspeaker drivers.

CapacitanceCapacitance

Capacitance. That property of a

CapacitanceCapacitance

capacitor which determines how
much charge can be stored in it
for a given potential difference
between its terminals, measured
in farads, by the ratio of the
charge stored to the potential
difference.

CapacitorCapacitor

Capacitor. A device consisting of two

CapacitorCapacitor

or more conducting plates
separated from one another by
an insulating material and used
for storing an electrical charge.
Sometimes called a condenser.

ClippingClipping

Clipping. Distortion of a signal by its

ClippingClipping

being chopped off. An overload
problem caused by pushing an
amplifier beyond its capabilities.
The flat-topped signal has high
levels of harmonic distortion
which creates heat in a loud­speaker and is the major cause
of loudspeaker component
failure.

CrossoverCrossover

Crossover. An electrical circuit that

CrossoverCrossover

divides a full bandwidth signal
into the desired frequency bands
for the loudspeaker components.

dB (decibel)dB (decibel)

dB (decibel). A numerical expression

dB (decibel)dB (decibel)

of the relative loudness of a
sound. The difference in decibels
between two sounds is ten times
the common logarithm of the ratio
of their power levels.

DCDC

DC. Abbreviation for direct current.

DCDC

DiffractionDiffraction

Diffraction. The breaking up of a

DiffractionDiffraction

sound wave caused by some
type of mechanical interference
such as a cabinet edge, grill
frame, or other similar object.

DiaphragmDiaphragm

Diaphragm. A thin flexible membrane

DiaphragmDiaphragm

or cone that vibrates in response
to electrical signals to produce
sound waves.

DistortionDistortion

Distortion. Usually referred to in

DistortionDistortion

terms of total harmonic distortion
(THD) which is the percentage of
unwanted harmonics of the drive
signal present with the wanted
signal. Generally used to mean
any unwanted change introduced
by the device under question.

DriverDriver

Driver. See transducer.

DriverDriver

Dynamic RangeDynamic Range

Dynamic Range. The range between

Dynamic RangeDynamic Range

the quietest and the loudest
sounds a device can handle
(often quoted in dB).

EfficiencyEfficiency

Efficiency. The acoustic power

EfficiencyEfficiency

delivered for a given electrical
input. Often expressed as
decibels/watt/meter (dB/w/m).

ESLESL

ESL. Abbreviation for electrostatic

ESLESL

loudspeaker.

HeadroomHeadroom

Headroom. The difference, in deci-

HeadroomHeadroom

bels, between the peak and RMS
levels in program material.

HybridHybrid

Hybrid. A product created by the

HybridHybrid

marriage of two different tech­nologies. Meant here as the
combination of a dynamic woofer
with an electrostatic transducer.

Hz (Hertz)Hz (Hertz)

Hz (Hertz). Unit of frequency equiva-

Hz (Hertz)Hz (Hertz)

lent to the number of cycles per
second.

ImagingImaging

Imaging. To make a representation or

ImagingImaging

imitation of the original sonic
event.

ImpedanceImpedance

Impedance. The total opposition

ImpedanceImpedance

offered by an electric circuit to the
flow of an alternating current of a
single frequency. It is a combina­tion of resistance and reactance
and is measured in ohms.
Remember that a speaker’s
impedance changes with
frequency, it is not a constant

Page30

Monolith III User's Manual

value.

InductanceInductance

Inductance. The property of an

InductanceInductance

electric circuit by which a varying
current in it produces a varying
magnetic field that introduces
voltages in the same circuit or in
a nearby circuit. It is measured in
henrys.

InductorInductor

Inductor. A device designed primarily

InductorInductor

to introduce inductance into an
electric circuit. Sometimes called
a choke or coil.

LinearityLinearity

Linearity. The extent to which any

LinearityLinearity

signal handling process is
accomplished without amplitude
distortion.

MidrangeMidrange

Midrange. The middle frequencies

MidrangeMidrange

where the ear is the most
sensitive.

Passive crossoverPassive crossover

Passive crossover. Uses no active

Passive crossoverPassive crossover

components (transistors, IC’s,
tubes) and needs no power
supply (AC, DC, battery) to
operate. The crossover in a
typical loudspeaker is of the
passive variety. Passive cross­overs consist of capacitors,
inductors and resistors.

PhasePhase

Phase. The amount by which one

PhasePhase

sine wave leads or lags a second
wave of the same frequency. The
difference is described by the
term phase angle. Sine waves in

phase reinforce each other; those
out of phase cancel.

Pink noisePink noise

Pink noise. A random noise used in

Pink noisePink noise

measurements, as it has the
same amount of energy in each
octave.

PolarityPolarity

Polarity. The condition of being

PolarityPolarity

positive or negative with respect
to some reference point or object.

RMSRMS

RMS. Abbreviation for root mean

RMSRMS

square. The effective value of a
given waveform is its RMS value.
Acoustic power is proportional to
the square of the RMS sound
pressure.

ResistanceResistance

Resistance. That property of a

ResistanceResistance

conductor by which it opposes
the flow of electric current,
resulting in the generation of heat
in the conducting material,
usually expressed in ohms.

ResistorResistor

Resistor. A device used in a circuit

ResistorResistor

primarily to provide resistance.

ResonanceResonance

Resonance. The effect produced

ResonanceResonance

when the natural vibration
frequency of a body is greatly
amplified by reinforcing vibrations
at the same or nearly the same
frequency from another body.

SensitivitySensitivity

Sensitivity. Volume of sound deliv-

SensitivitySensitivity

ered for a given electrical input.

StatorStator

Stator. The fixed part forming the

StatorStator

reference for the moving dia­phragm in a planar speaker.

THDTHD

THD. Abbreviation for total harmonic

THDTHD

distortion. (See Distortion.)

TIMTIM

TIM. Abbreviation for transient

TIMTIM

intermodulation distortion. (See
Distortion.)

TransducerTransducer

Transducer. Any of various devices

TransducerTransducer

that transmit energy from one
system to another, sometimes
one that converts the energy in
form. Loudspeaker transducers
convert electrical energy into
mechanical motion.

TransientTransient

Transient. Applies to that which lasts

TransientTransient

or stays but a short time. A
change from one steady-state
condition to another.

TransmitTransmit

Transmit. To cause sound to pass

TransmitTransmit

through air or some other
medium.

TweeterTweeter

Tweeter. A small drive unit designed

TweeterTweeter

to produce only high frequencies.

WavelengthWavelength

Wavelength. The distance measured

WavelengthWavelength

in the direction of progression of
a wave, from any given point
characterized by the same phase.

White noiseWhite noise

White noise. A random noise used in

White noiseWhite noise

measurements, as it has the
same amount of energy at each
frequency.

WooferWoofer

Woofer. A drive unit operating in the

WooferWoofer

bass frequencies only. Drive
units in two-way systems are not
true woofers but are more
accurately described as being
mid/bass drivers.

Monolith III User's Manual

Page31

$ 3.00

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© 1989 Martin-Logan Ltd. All rights reserved.