MartinLogan Monolith III user manual IIIx Connection, Introduction, Packaging

IIIx Connection

Introduction

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 perform- ance. 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 differ- ences between a single amplified system versus a properly interfaced bi- amplified 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 full- bandwidth 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 cross- over, 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 advan- tages. 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 (intermodu- lation 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.

Warnings

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 Martin- Logan dealer only.

Packaging

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.

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