Behringer Stereo Amplifier MDX4400 User Manual

User’s Manual  
Version 1.3 April 2001  
 
MULTICOM PRO MDX4400  
FOREWORD  
Dear Customer,  
Welcome to the team of MULTICOM PRO users and thank you very much for expressing your confidence in  
BEHRINGER products by purchasing this unit.  
It is one of my most pleasant tasks to write this letter to you, because it is the culmination of many months of  
hard work delivered by our engineering team to reach a very ambitious goal: making an outstanding device  
better still. The MULTICOM has for quite a long time been a standard tool used by numerous studios and  
PA rental companies. The task to improve one of our best-selling products certainly meant a great deal of  
responsibility, which we assumed by focusing on you, the discerning user and musician. It also meant a lot of  
work and night shifts to accomplish this goal. But it was fun, too. Developing a product usually brings a lot of  
people together, and what a great feeling it is when everybody who participated in such a project can be proud  
of what we’ve achieved.  
It is our philosophy to share our joy with you, because you are the most important member of the BEHRINGER  
family. With your highly competent suggestions for new products you’ve greatly contributed to shaping our  
company and making it successful. In return, we guarantee you uncompromising quality (manufactured under  
the ISO9000 certified management system) as well as excellent technical and audio properties at an  
extremely favorable price. All of this will enable you to fully unfold your creativity without being hampered by  
budget constraints.  
We are often asked how we can make it to produce such high-grade devices at such unbelievably low prices.  
The answer is quite simple: it’s you, our customers! Many satisfied customers means large sales volumes  
enabling us to get better conditions of purchase for components, etc. Isn’t it only fair to pass this benefit back  
to you? Because we know that your success is our success, too!  
I would like to thank all people whose help on “Project MULTICOM PRO” has made it all possible. Everybody  
has made very personal contributions, starting from the designers of the unit via the many staff members in our  
company to you, the user of BEHRINGER products.  
My friends, it’s been worth the trouble!  
Thank you very much,  
Uli Behringer  
3
 
MULTICOM PRO MDX4400  
®
MULTICOM PRO  
Interactive 4-channel compressor/limiter/peak limiter of the reference class  
s
IKA (Interactive Knee Adaptation) compressor concept combines the advantages of “hard knee” and  
“soft knee” characteristics  
s
Switchable highpass filter in control signal path avoids low-frequency signals from dominating compressor  
action  
s
s
s
s
s
s
s
s
s
4
Compression characteristics switchable between IKA and “hard knee” characteristics  
IGC (Interactive Gain Control) peak limiter combines clipper with program limiter circuits  
Extremely low-noise operational amplifiers and high-grade VCA’s  
High-quality detent potentiometers and backlit switches  
Stereo Couple function for channels 1/2 and 3/4 selectable with real totaling of RMS output  
Accurate 8-digit LED meters for input level, output level and gain reduction  
Operating level switchable from +4 dBu to -10 dBV  
Servo-balanced inputs and outputs featuring 1/4" jacks and XLR connectors  
Manufactured under ISO9000 certified management system  
 
MULTICOM PRO MDX4400  
TABLE OF CONTENT  
1. INTRODUCTION.....................................................................................................................6  
1.1 Technical Background ..................................................................................................................... 7  
1.1.1 Noise As A Physical Phenomenon ........................................................................................ 7  
1.1.2 WhatAre Audio Dynamics? .................................................................................................. 7  
1.1.3 Compressors/Limiters ........................................................................................................... 9  
2. THE DESIGN CONCEPT .....................................................................................................10  
2.1 High Quality ComponentsAnd Design........................................................................................... 10  
2.2 InputsAnd Outputs ....................................................................................................................... 10  
2.2.1 Balanced InputsAnd Outputs.............................................................................................. 10  
3. INSTALLATION ..................................................................................................................... 11  
3.1 Rack Mounting............................................................................................................................... 11  
3.2 Mains Voltage ................................................................................................................................ 11  
3.3 Audio Connections ......................................................................................................................... 11  
3.4 Selecting The Operating Level ....................................................................................................... 12  
4. CONTROLS ..........................................................................................................................13  
4.1 The Front Panel Control Elements ................................................................................................ 13  
4.4 Rear Panel Control Elements Of The MULTICOM PRO ................................................................. 15  
5. APPLICATIONS .....................................................................................................................16  
5.1 Compression/Leveling/Limiting/Clipping ......................................................................................... 16  
5.2 Compressor Section ..................................................................................................................... 17  
5.2.1 Initial Settings For The Compressor Section ....................................................................... 18  
5.2.2 The MULTICOM PROAsASound Effects Unit .................................................................... 18  
5.2.3 The “Muffling” Effect OfACompressor ................................................................................. 18  
5.3 Peak Limiter Section..................................................................................................................... 19  
5.3.1 Initial Settings For The Peak Limiter Section....................................................................... 19  
6. SPECIALAPPLICATIONS.....................................................................................................20  
6.1 Using The MULTICOM PRO For RecordingAnd Cassette Duplication ........................................... 20  
6.1.1 The MULTICOM PRO In Digital RecordingAnd Sampling .................................................... 20  
6.1.2 The MULTICOM PRO In Mastering ...................................................................................... 20  
6.2 The MULTICOM PRO as a protective device .................................................................................. 20  
6.2.1 Protection OfA System With APassive Crossover .............................................................. 21  
6.2.2 Protection OfASystem WithAn Active Crossover............................................................... 21  
6.2.3 Improving The Sound OfAProcessor System ..................................................................... 21  
6.3 The MULTICOM PRO In Broadcast ............................................................................................... 22  
7. SPECIFICATIONS..................................................................................................................23  
8. WARRANTY ...........................................................................................................................25  
5
 
MULTICOM PRO MDX4400  
1. INTRODUCTION  
In purchasing the MULTICOM PRO, you have acquired an extremely efficient and universal dynamics  
processor. The unit was particularly designed for those applications most frequently used in practice. Despite  
the extremely complex internal circuitry, the unit has a control surface which is clearly laid out and easy to  
understand. With the MULTICOM PRO, BEHRINGER have developed an innovative and easy-to-use dynamics  
processor which meets the high demands that are made on such a device both in live and studio applications.  
The unit’s most outstanding features are the precision and flexibility of its functions.  
Quad compressor/limiters are actually not a new invention. Usually, four simple compressor sections are  
packed into one enclosure, representing however a compromise in terms of operation and functionality. An  
excessive number of controls complicates the operation of the unit and a lack of control functions restricts the  
unit’s range of application.  
The BEHRINGER MULTICOM PRO is a compact quad compressor/limiter based on the successful BEHRINGER  
Interactive Technology. Integrated AUTO processors automatically derive attack and release times from the  
programme material and provide you with transparent and “inaudible” compression. In 1 RU package the unit  
consists of four independent high-precision compressor sections with sidechain filters and four peak limiters,  
each offering all the required controls.  
With rack space at a premium both in the studio and in sound reinforcement, the MULTICOM PRO’s unique  
high density design and clean uncluttered layout makes it a truly useful audio tool for all applications. The  
MULTICOM PRO is a perfect and extremely cost-effective solution for all your multi-channel dynamic  
applications.  
Advanced BEHRINGER Technology  
Compared to its predecessors, the MULTICOM PRO offers several advanced features such as the extended  
LED meters, the sidechain filter, the controlable peak limiter per channel and the couple function for two  
channels. Additionally, we have succeeded in refining the audio properties as well as the circuit topology.  
For the first time, the MULTICOM PRO MDX 4400 uses SMD technology (Surface Mounted Device). These  
sub-miniature components known from aerospace technology allow for an extreme packing density, plus  
improve the unit’s reliability.  
IKA (Interactive Knee Adaptation) Compressor  
Our proven IKA (Interactive Knee Adaptation) circuit successfully combines the concept of a “hard knee”  
compressor with the characteristics of a “soft knee” approach. This program-dependent regulation scheme  
forms the prerequisite both for “inaudible” and musical program compression and for creative and highly  
effective dynamics processing.  
With its IKA circuit the MULTICOM PRO is capable of delivering outstanding musical results both in studio and  
live PA applications.  
Additionally, the MULTICOM PRO’s sidechain filter allows for limiting the influence low-frequency signal  
portions usually have on the control logic, so that the compression ratio is mainly determined by those  
frequencies that are essential to the loudness perceived by the listener—the midrange frequencies.  
AUTO COMPRESSOR Circuitry  
The response of a compressor and the quality of dynamics processing largely depend on the control times,  
i.e., the attack and release functions. In particular, in the field of “musical” compression of complex composite  
signals, programme-dependent control times are necessary. The interactive AUTO processor derives the  
attack and release times automatically from the programme material, a function that avoids misadjustment of  
the control times, which is a problem often encountered in conventional designs. In addition the AUTO  
processor allows for a high compression of the dynamic range without any audible side effects, such as  
“pumping”, “breathing” etc.  
IGC (Interactive Gain Control) Peak Limiter  
A further remarkable feature of the BEHRINGER MULTICOM PRO is the IGC (Interactive Gain Control) Limiter,  
an intelligent combination of a clipper and a program limiter. Above an adjustable threshold the peak limiter  
begins to function and restricts signal peaks radically (clipper). If however, the threshold of the limiter was  
surpassed for more than a few milliseconds, the IGC circuit automatically kicks in and reduces the level of the  
6
1. INTRODUCTION  
 
MULTICOM PRO MDX4400  
overall output signal so that no audible distortion occurs (program limiter). After the level falls below the thresh-  
old, the signal returns to the original value after a period of about 1 second. This IGC circuit proves to be  
extremely valuable as much for live work (loudspeaker protection) as for digital situations, where any extreme  
signal peaks would exceed the maximum headroom and therefore would cause severe problems.  
+
The following instructions should initially familiarize you with the special terms used, so that  
you can get to know all the functions of the unit. After you have read the instructions carefully,  
please put them away safely, so that you can refer to them again if necessary.  
1.1 Technical Background  
By employing current modern analogue technology it is possible to manufacture audio equipment with a  
dynamic range of up to 125 dB. In contrast to analogue techniques, the dynamic range of digital equipment is  
approximately 25 dB less. With conventional record and tape recorder technology, as well as broadcasting,  
this value is further reduced. Generally, dynamic restrictions are due to noisy storage in transmission media  
and also the maximum headroom of these systems.  
1.1.1 Noise As A Physical Phenomenon  
All electrical components produce a certain level of inherent noise. Current flowing through a conductor leads  
to uncontrolled random electron movements. For statistical reasons, this produces frequencies within the  
whole audio spectrum. If these currents are highly amplified, the result will be perceived as noise. Since all  
frequencies are equally affected, we term this white noise. It is fairly obvious that electronics cannot function  
without components. Even if special low-noise components are used, a certain degree of basic noise cannot  
be avoided.  
This effect is similar when replaying a tape. The non-directional magnetic particles passing the replay head can  
also cause uncontrolled currents and voltages. The resulting sound of the various frequencies is heard as  
noise. Even the best possible tape biasing can “only” provide signal-to-noise ratios of about 70 dB, which is not  
acceptable today since the demands of listeners have increased. Due to the laws of physics, improving the  
design of the magnetic carrier is impossible using conventional means.  
1.1.2 What Are Audio Dynamics?  
A remarkable feature of the human ear is that it can detect the most wide ranging amplitude changes—from the  
slightest whisper to the deafening roar of a jet-plane. If one tried to record or reproduce this wide spectrum of  
sound with the help of amplifiers, cassette recorders, records or even digital recorders (CD, DAT etc.), one  
would immediately be restricted by the physical limitations of electronic and acoustic sound reproduction  
technology.  
The usable dynamic range of electro-acoustic equipment is limited as much at the low end as at the high end.  
The thermal noise of the electrons in the components results in an audible basic noise floor and thus repre-  
sents the bottom limit of the transmission range. The upper limit is determined by the levels of the internal  
operating voltages; if they are exceeded, audible signal distortion is the result. Although in theory, the usable  
dynamic range sits between these two limits, it is considerably smaller in practice, since a certain reserve  
must be maintained to avoid distortion of the audio signal if sudden level peaks occur. Technically speaking,  
we refer to this reserve as “headroom”—usually this is about 10 - 20 dB. A reduction of the operating level would  
allow for greater headroom, i.e. the risk of signal distortion due to level peaks would be reduced. However, at  
the same time, the basic noise floor of the program material would be increased considerably.  
1. INTRODUCTION  
7
 
MULTICOM PRO MDX4400  
P/dB  
140  
120  
100  
80  
60  
40  
Fig. 1.1: The dynamic range capabilities of various devices  
It is therefore useful to keep the operating level as high as possible without risking signal distortion in order to  
achieve optimum transmission quality.  
It is possible to further improve the transmission quality by constantly monitoring the program material with the  
aid of a volume fader, which manually levels the material. During low passages the gain is increased, during  
loud passages the gain is reduced. Of course it is fairly obvious that this kind of manual control is rather  
restrictive; it is difficult to detect signal peaks and it is almost impossible to level them out. Manual control is  
simply not fast enough to be satisfactory.  
P/dB  
Clipping  
+20  
Headroom  
0
Operating level  
-20  
-40  
Effective SNR  
-60  
-80  
Noise floor  
t
Fig. 1.2: The interactive relationship between the operating level and the headroom  
The need therefore arises for a fast acting automatic gain control system which will constantly monitor the  
signals and which will always adjust the gain to maximize the signal-to-noise ratio without incurring signal  
distortion. This device is called a compressor or limiter. This system is a part of the BEHRINGER MULTICOM  
PRO.  
8
1. INTRODUCTION  
 
MULTICOM PRO MDX4400  
1.1.3 Compressors/Limiters  
By measuring the dynamic range of musical instruments in live recording situations, you will find that extreme  
amplitudes occur which often lead to overload in subsequent signal processing equipment. Especially in  
broadcasting and record cutting techniques, these signal peaks can lead to heavy distortion. To avoid this kind  
of distortion or, for example, to avoid loudspeakers being damaged by overload, compressors or limiters are  
used.  
The principal function used in these devices is dependent on an automatic gain control as mentioned in the  
previous section, which reduces the amplitude of loud passages and therefore restricts the original dynamics  
to a desired range. This application is particularly useful in microphone recording techniques, to compensate  
for level changes which are caused by varying microphone distances. Although compressors and limiters  
perform similar tasks, one essential point makes them different: limiters abruptly limit the signal above a  
certain level, while compressors control the signal “gently” over a wider range. A limiter continuously monitors  
the signal and intervenes as soon as the level exceeds a user-adjustable threshold. Any signal exceeding this  
threshold will be immediately returned to the adjusted level.  
A compressor also monitors the program material continuously and has a certain threshold level. With com-  
pression, in contrast to the action of a limiter, signals are not reduced in level abruptly once the threshold has  
been exceeded, but are returned to the threshold gradually. The signal is reduced in gain, relative to the  
amount the signal exceeds this point.  
Generally, threshold levels for compressors are set below the normal operating level to allow for the upper  
dynamics to be musically compressed. For limiters, the threshold point is set above the normal operating level  
in order to provide reliable signal limiting, to protect subsequent equipment from signal overload.  
1. INTRODUCTION  
9
 
MULTICOM PRO MDX4400  
2. THE DESIGN CONCEPT  
2.1 High Quality Components And Design  
The philosophy behind BEHRINGER products guarantees a no-compromise circuit design and employs the  
best choice of components. The operational amplifiers NJM4580 which are used in the MULTICOM PRO, are  
exceptional. They boast extreme linearity and very low distortion characteristics. The most important aspect of  
the MULTICOM PRO design is a radical VCA implementation which results in outstanding technical specifica-  
tion and excellent performance. To complement this design the choice of components includes high tolerance  
resistors and capacitors, detent potentiometers and several other stringently selected elements.  
For the first time, the MULTICOM PRO MDX 4400 uses SMD technology (Surface Mounted Device). These  
sub-miniature components known from aerospace technology allow for an extreme packing density, plus the  
unit’s reliability could be improved. Additionally, the unit is manufactured under ISO9000 certified management  
system.  
2.2 Inputs And Outputs  
2.2.1 Balanced Inputs And Outputs  
As standard, the BEHRINGER MULTICOM PRO is installed with electronically servo-balanced inputs and  
outputs. The new circuit design features automatic hum and noise reduction for balanced signals and thus  
allows for trouble-free operation, even at high operating levels. Externally induced mains hum etc. will be  
effectively suppressed. The automatic servo-function recognizes the presence of unbalanced connectors and  
adjusts the nominal level internally to avoid level differences between the input and output signals (correction 6  
dB).  
10  
2. THE DESIGN CONCEPT  
 
MULTICOM PRO MDX4400  
3. INSTALLATION  
Your BEHRINGER MULTICOM PRO was carefully packed in the factory and the packaging was designed to  
protect the unit from rough handling. Nevertheless, we recommend that you carefully examine the packaging  
and ist contents for any signs of physical damage, which may have occurred in transit.  
Please also take the time to complete and return the warranty card within 14 days of the date of purchase,  
otherwise you will lose the right to the extended warranty. Or simply use our online registration under  
+
If the unit is damaged, please do not return it to us, but notify your dealer and the shipping  
company immediately, otherwise claims for damage or replacement may not be granted.  
Shipping claims must be made by the consignee.  
3.1 Rack Mounting  
The BEHRINGER MULTICOM PRO fits into one standard 19" rack unit of space (1 3/4"). Please allow at least  
an additional 4" depth for the connectors on the back panel. Be sure that there is enough air space around the  
unit for cooling and please do not place the MULTICOM PRO on high temperature devices such as power  
amplifiers etc. to avoid overheating.  
3.2 Mains Voltage  
Before you connect your MULTICOM PRO to the mains, please make sure that your local voltage  
matches the voltage required by the unit! The fuse holder on the female mains connector has 3 triangular  
markers, with two of these triangles opposing each other. Your MULTICOM PRO is set to the operating voltage  
printed next to these markers, and can be set to another voltage by turning the fuse holder by 180°. CAUTION:  
this instruction does not apply to export models exclusively designed, e.g. for 115 V operation!  
3.3 Audio Connections  
The audio inputs and outputs on the BEHRINGER MULTICOM PRO are fully balanced. If possible, connect the  
unit to other devices in a balanced configuration to allow for maximum interference immunity.  
+
Please ensure that only qualified persons install and operate the VIRTUALIZER. During instal-  
lation and operation the user must have sufficient electrical contact to earth. Electrostatic  
charges might affect the operation of the MULTICOM PRO!  
Output  
Cable  
Input  
Ground  
Positive  
Negative  
Pin 1  
2
1
1
2
Shield  
(+) Signal + Hum  
(-) Signal + Hum  
Pin 2 = (+) Signal  
Pin 3 = (-) Signal  
(+)Hum + Signal  
(-)Hum + Signal  
3
3
2 x Signal  
= Signal + 6 dB  
RFI and Hum  
Fig. 3.1: Compensation of interference with balanced connections  
3. INSTALLATION  
11  
 
MULTICOM PRO MDX4400  
Unbalanced use of  
Balanced use of  
mono 1/4" jack plugs  
stereo 1/4" jack plugs  
Tip =  
Signal  
Tip =  
hot (+ve)  
Ring =  
cold (-ve)  
Sleeve =  
Ground / Shield  
Sleeve =  
Ground / Shield  
Tip  
Tip  
Ring  
Sleeve  
Sleeve  
Strain relief clamp  
Strain relief clamp  
For connection of balanced and  
unbalanced plugs, ring and sleeve have  
to be bridged at the stereo plug.  
Balanced use with XLR connectors  
2
1
1
2
1 = Ground / Shield  
2 = hot (+ve)  
3 = cold (-ve)  
3
3
Input  
Output  
For unbalanced use pin 1 and pin 3 have to be bridged  
Fig. 3.2: Different plug types  
+
Never use unbalanced XLR connections with microphone cables, as this would short-circuit  
any phantom power transmitted over these cables!  
3.4 Selecting The Operating Level  
With the “Operating Level” switch on the rear of the BEHRINGER MULTICOM PRO you can adjust the internal  
operating level of the unit. Thus, the MULTICOM PRO can be adapted perfectly to various levels (e.g. both the  
typical home recording level of -10 dBV and the professional level of +4 dBu). The level meters are referenced  
automatically to the selected level, i.e. an optimum operating range of the meters will always be ensured.  
12  
3. INSTALLATION  
 
MULTICOM PRO MDX4400  
4. CONTROLS  
Fig. 4.1: MULTICOM PRO front panel  
The BEHRINGER MULTICOM PRO has four identical channels. Each channel is equipped with 4 backlit push-  
buttons, 4 rotary controls and 17 LED’s. The COUPLE switches are for stereo operation of two channels.  
4.1 The Front Panel Control Elements  
11  
8
10  
7
1
6
2
5
3
4
9
Fig. 4.2: Control elements on the front panel  
1
2
The THRESHOLD control sets the threshold point for the compressor section. It has a range of -40 to  
+20 dB. If the channel is switched to INTERACTIVE mode (Interactive Knee Adaptation), a “Soft Knee”  
characteristic is applied to the signal exceeding the threshold point by a maximum of 10 dB. Above 10  
dB, the signal would experience “Hard Knee” compression.  
The RATIO control determines the ratio between the input and output level for all signals exceeding the  
threshold point. If the INTERACTIVE mode is used, this control determines the ratio between input and  
output levels for signals exceeding the threshold point by more than 10 dB. The control range can be  
adjusted from 1:1 to oo:1.  
3
The OUTPUT control allows for the increase or decrease of the output signal by a maximum of 20 dB.  
Thus, a level loss due to the compression or limiting process can be compensated for.  
+
Please note when using the THRESHOLD control of the Peak Limiter section, that the OUTPUT  
control of the Compressor section precedes the Peak Limiter section. If the OUTPUT control is  
set too high, this can result in continuous peak limiting (see item 9 “THRESHOLD control”).  
4
The IN/OUT switch activates the corresponding channel. This switch acts as a so-called “hard-bypass”  
switch, which means that when the switch is OUT, the input jack is directly linked to the output jack.  
Normally, this switch is used to perform a direct A/B comparison between the unprocessed and the  
compressed or limited signals.  
5
6
Press the INTERACTIVE switch to change from “Hard Knee” to IKA characteristics. IKA provides a very  
subtle and musical compression of the program material and should therefore be used whenever  
compression should be more or less inaudible.  
The SC FILTER switch activates a highpass filter in the sidechain path and thus limits the influence of  
low frequencies on the MULTICOM PRO’s control processes.  
4. CONTROLS  
13  
 
MULTICOM PRO MDX4400  
7
8
The 8-digit GAIN REDUCTION meter indicates how effectively the gain is reduced by the compressor,  
within a range from 1 to 30 dB.  
The 8-digit INPUT/OUTPUT LEVEL meter informs you—depending on the setting of the I/O METER  
switch—about the current input or output level, within a range from -24 to +18 dB. When the switch is  
set to IN (not engaged), the meter reads the input level, when it is OUT, the output level is displayed. The  
meter is referenced to the operating level (-10 dBV or +4 dBu) adjusted with the OPERATING LEVEL  
switch on the back.  
9
The peak limiter limits the signal to a level adjusted with the THRESHOLD control. Owing to its  
extremely fast response (“Zero” attack), the limiter is capable of limiting signal peaks without audible  
distortion. Whenever the signal is limited for more than 20 ms, the overall level is reduced for about 1  
second to avoid heavy and thus audible signal distortion.  
+
When you use the peak limiter as a protective device against signal peaks, the THRESHOLD  
control should be set in combination with the OUTPUT control in the compressor section so  
that the peak limiter responds rarely or not at all. Thus, only real signal peaks will activate the  
limiter circuit. However, to produce creative sound effects, the peak limiter can be  
deliberately set to lower levels.  
10  
11  
The LIM LED lights up as soon as the limiter function is activated.  
The MULTICOM PRO converts two channels to stereo mode by engaging one of the COUPLE switches,  
where the left of the channels assumes the control of both audio channels, i.e. the control signal of  
channel 2 is replaced with that of channel 1. By pressing the COUPLE switch, you override all the  
controls and switches of channel 2 (or 4) with the exception of the IN/OUT and SC Filter switches as well  
as the peak limiter’s THRESHOLD control. The controls of channel 1 (or 3) take over all functions of  
channel 2 (or 4).  
14  
4. CONTROLS  
 
MULTICOM PRO MDX4400  
4.4 Rear Panel Control Elements Of The MULTICOM PRO  
12  
16  
13  
15  
Fig. 4.5: Control elements of the rear panel  
14  
12  
FUSE HOLDER / VOLTAGE SELECTOR. Please make sure that your local voltage matches the volt-  
age indicated on the unit, before you attempt to connect and operate the MULTICOM PRO. Blown fuses  
may only be replaced by fuses of the same type and rating.  
13  
14  
15  
16  
MAINS CONNECTION. Use the enclosed power cord to connect the unit to the mains. Please also note  
the instructions given in the “INSTALLATION” chapter.  
AUDIO IN. These are the audio inputs of your MULTICOM PRO, available both as balanced 1/4" jack  
and XLR connectors.  
AUDIO OUT. These are the audio outputs of your MULTICOM PRO. Matching phone jack and XLR  
connectors are wired in parallel.  
With the OPERATING LEVEL switch you can adapt the MULTICOM PRO to various operating levels,  
i.e. you can select both the -10 dBV home recording level and the professional studio level of +4 dBu.  
The level meters are referenced automatically to the selected level, i.e. an optimum operating range of  
the meters will always be ensured.  
4. CONTROLS  
15  
 
MULTICOM PRO MDX4400  
5. APPLICATIONS  
In this section, several typical applications of the BEHRINGER MULTICOM PRO are discussed. The following  
basic settings can resolve most dynamic problems. They are the ideal starting point. Please take the time to  
study the application examples carefully, in order to be able to make full use of the MULTICOM PROs capabili-  
ties in the future.  
Main Applications And Initial Settings  
The main applications of the BEHRINGER MULTICOM PRO can be divided into two categories: The compressor  
section is used to compress the program material and to create special effects and unusual sounds, which are  
used for recording and musical performance. The subsequent Peak Limiter section is designed to protect  
loudspeakers, tape recorders, transmitters etc. from being overloaded.  
5.1 Compression/Leveling/Limiting/Clipping  
Now that the functions of the individual sections have been clearly explained, we would like to acquaint you  
with more terms and relationships of the dynamics process.  
Compression  
A compressor converts a large dynamic level into a restricted range. The extent of the resulting dynamic level  
is dependent on the threshold, attack, release and ratio settings. As it is the desired effect of a compressor to  
increase a low level signal, generally the threshold is set low. The “inaudible” compression mode requires fast  
attack and release times and low ratios. The faster the chosen control times and the higher the compression  
ratio, the greater the effect on the short term dynamics. This fact is often used to achieve audible and creative  
sound effects.  
Leveling  
The leveling mode is used to keep output level constant, i.e. to compensate for long term gain changes, without  
affecting the short term dynamics. Normally, the threshold is set quite low in order to be able to increase low  
level signals. Leveling requires slow attack and release times, combined with a high ratio. Because of the very  
slow response time, leveling has no effect on signal peaks or short term changes in average level.  
Limiting  
The limiting function requires a fast attack time and a high ratio and release time setting, which is dependent  
on the specific use and the desired sound effect. As it is usually the task of a limiter to limit only high signal  
peaks, the threshold is usually set at a high level. The dynamics are reduced dependent on the ratio setting  
and the degree by which the threshold point was exceeded. If the attack time is adjusted to control only the  
average level without affecting signal peaks above the threshold, this is referred to as the program limiter. For  
this purpose the attack time will be set above 20 ms. If the attack time is further reduced in order to also control  
signal peaks, this is defined as the peak limiter.  
Clipping  
In contrast to the two previously mentioned limiters, the clipping mode features infinitely fast control times, an  
infinite compression ratio and creates an unsurpassable barrier (“brickwall”) for all signals above a certain level.  
To be able to control the signal peaks, the clipping function radically cuts signals above the threshold, without  
affecting the amplitude of the original signal. If used in normal applications, this function remains inaudible and  
under certain circumstances it can even lead to an improved sound, because cutting the transients creates  
artificial harmonics. If misused, clipping can cause very obvious and distasteful distortion, which in an extreme  
manner, will convert the signal’s waveform into a square wave signal. This effect is often produced in guitar  
distortion devices (“fuzz boxes”).  
16  
5. APPLICATIONS  
 
MULTICOM PRO MDX4400  
5.2 Compressor Section  
The task of a compressor is to reduce the dynamic range of program material and to control the overall level.  
The extensive controls of the Compressor section, provide a great range of dynamic effects: from musical and  
soft compression to limiting signal peaks, right up to extreme and effective compression of the overall  
dynamics. For example, a low ratio and very low threshold setting can be used to achieve soft and musical  
processing of the general dynamics of the program material.  
Higher ratios, together with low threshold settings, create relatively constant volume (leveling) for instruments  
and vocals. High threshold levels generally limit the overall level of a program. Ratios greater than 6:1 effectively  
prevent the output level from significantly exceeding the threshold point (provided that the OUTPUT control is in  
the 0 dB position).  
Please note that the compression of the entire program material (achieved by low threshold settings) sounds  
less natural with higher ratio settings. Ratio settings in the range of 4:1 and lower, effect the dynamics of the  
program material less and are often used to compress the sound of a bass guitar, a snare drum or a vocal.  
Sensitive and moderate settings are generally used in mixing and for leveling of program material in broadcast.  
Output  
Gain 0 dB  
Threshold  
Ratio 2:1  
Hard Knee  
Ratio 4:1  
Limiter  
oo:1  
IKA Curve  
Input  
Fig. 5.1: IKA characteristic of the compressor section  
The new IKA (Interactive Knee Adaptation) circuit prevents aggressive compression, created by high ratios,  
from sounding too unnatural. This is achieved with an interactive control function, which begins above the  
threshold level and introduces a “Soft Knee” curve characteristic in the range up to 10 dB above the threshold  
point. Beyond this range, the signal is subjected to linear (“Hard Knee”) compression.  
+
With the threshold control completely turned to the right, the threshold value is +20 dB. Since  
such a value will not be reached in practice, you can use it to disable the compressor section  
and work exclusively with the limiter circuits.  
5. APPLICATIONS  
17  
 
MULTICOM PRO MDX4400  
5.2.1 Initial Settings For The Compressor Section  
Control  
Setting  
IN  
IN/OUT switch  
INTERACTIVE switch  
SC FILTER switch  
THRESHOLD control  
RATIO control  
IN  
OUT  
+20 dB  
3:1  
OUTPUT control  
0 dB  
Tab. 5.1: Initial settings for the compressor section  
Rotate the THRESHOLD control counterclockwise until an appropriate amount of gain reduction is indicated on  
the GAIN REDUCTION meter. This operation will be accompanied by an audible drop in output level. The  
OUTPUT control should now be turned clockwise to reinstate the output level. The level of the unprocessed and  
the processed signal can be compared by pressing the I/O METER switch and observing the INPUT/OUTPUT  
LEVEL meter.  
Final adjustments of the RATIO control can then be made to suit your particular requirements. The experi-  
enced user will be in a position to specify parameters while in bypass mode and thus realize the effect before  
the unit is actually switched into operation. This is important in live situations, where a signal needs to be  
managed efficiently by the engineer, without the convenience of continual A/B comparison.  
5.2.2 The MULTICOM PRO As A Sound Effects Unit  
In the early 1960’s, musicians began looking at the recording process as a way to create new sounds. The  
pumping effect which had been avoided by earlier engineers suddenly became fashionable and was utilized as  
a creative tool, laying the groundwork for many of the sounds which are now considered indispensable in  
contemporary music. The compressor is used in this role because you can hear it working, and control of the  
dynamic range is of secondary importance.  
The BEHRINGER MULTICOM PRO, with its extensive range of functions, is well suited to this application.  
Sound effects of this kind can be achieved using “extreme” settings. To achieve this, set the THRESHOLD  
control to a fairly low level, the RATIO control to almost maximum to obtain the desired effect. Experiment with  
all the controls in order to get a feel of their function!  
5.2.3 The “Muffling” Effect Of A Compressor  
Quite often, compressors are sometimes accused of “muffling” the sound, whilst at the same time reducing the  
dynamics. This fact should be investigated further. Bass frequencies contain most of the energy within music  
and therefore cause the compressor to reduce the overall dynamics. If the music also contains high frequen-  
cies along with the bass frequencies, these are also reduced in level. This is the reason why: in an extremely  
compressed recording of drums, the cymbals and high-hats are acoustically swamped by the sound of the  
snare or the bass drum. The same effect is experienced when processing reverberated or ambient sounds. The  
solution commonly used to this basic problem is either to reduce the compression ratio or to slow down the  
attack time, so that the increasing high frequency transients pass through the compressor unhindered before  
the compressor takes effect.  
The MULTICOM PRO MDX4400 offers a solution to this problem that is by much more elegant. The SC Filter  
switch allows you to activate a highpass filter in the control signal path of the compressor. This filter makes  
sure that midrange and treble range frequencies are taken into account to a greater extent, and that a low-  
frequency signal triggers less compression than a midrange/treble signal of comparable level. A major advan-  
tage of this design can be seen in the fact that the frequency response of the overall signal is not modified  
below the threshold adjusted with the Threshold control.  
18  
5. APPLICATIONS  
 
MULTICOM PRO MDX4400  
In pop music the dynamics of both kick drum and bass guitar are usually processed individually. The sidechain  
filter is therefore ideally suited to apply overall compression in the mixdown, to compress the music while  
increasing its loudness, but without having to accept the drawbacks described above.  
Please note that we offer a whole series of high-grade equalizers and enhancers/exciters, which are perfect  
tools to give any dynamics-processed signal the finishing acoustic touch. Please ask for detailed information!  
5.3Peak Limiter Section  
As a section of its own and independent of the remaining control functions, the peak limiter enables you to limit  
the maximum peak level on the MULTICOM PRO’s output. It has been designed for use in combination with the  
compressor section. Independently of all compressor functions, you can protect subsequent devices against  
signal peaks, short-time overload and excess modulation (radio stations, etc.).  
Peak Limiting  
Level  
Program Limiting  
Input  
Release  
Threshold  
Output  
5 ms  
20  
approx. 1 s  
20 ms  
10  
30  
t/ms  
Fig. 5.3: IGC characteristic of the limiter section  
The diagram illustrates the functioning of the IGC limiter. The solid graph represents the output signal, while the  
dashed graph above shows the input signal response. The areas between the graphs represent the amount of  
gain reduction (bright areas are “clipping areas”, i.e. signal peaks are radically cut off, dark areas show the  
effect of the program limiter). The limiter is activated when the adjusted threshold is exceeded for more than 20  
ms, so as to limit audible clipping to a very short moment. About 1 s after the signals has dropped below the  
threshold again, the reduction is set to 0 dB, so that input and output signals are identical again (unity gain).  
5.3.1 Initial Settings For The Peak Limiter Section  
Control  
Setting  
OFF  
THRESHOLD control  
Tab. 5.3: Initial settings for the peak limiter section  
The THRESHOLD control of the Peak Limiter sets the threshold level, so that subsequent units are protected  
from overloading. If the LIM comes on regularly or is on constantly, the OUTPUT control of the compressor  
section must be turned down, as this control sets the level of the signal, which is routed to the Peak Limiter  
section.  
If this technique leads to an undesired drop in the overall level, it is recommended that you increase the  
compression: either, reduce the threshold level, or increase the compression ratio with the RATIO control. The  
OUTPUT control will compensate for a renewed drop in level.  
5. APPLICATIONS  
19  
 
MULTICOM PRO MDX4400  
6. SPECIAL APPLICATIONS  
6.1 Using The MULTICOM PRO For Recording And Cassette Duplication  
In the recording and duplication field the goal should always be to achieve an optimum recording level onto the  
recording media. Too low or too high recording levels lead to side effects such as noise, distortion etc. In  
mastering and multitrack recording, as well as in duplication, one should always take care to utilize the full  
dynamic range of the tape recorder, DAT recorder etc. Principally, it is possible to control the recording level by  
“riding” faders, which means with low level signals, the gain is increased, whereas the amplitude of high level  
signal is reduced. It is obvious that this method is insufficient because, especially in live recordings, the  
expected signal levels cannot be anticipated correctly. Especially with multitrack recordings, which are run  
under hectic circumstances, the signal level of all channels cannot be monitored and controlled at the same  
time. Generally, with manual control, it is not possible to achieve satisfying recording results.  
An automatic gain control system achieves better and more constant results. Use the MULTICOM PRO by  
starting with the initial settings, and use its dynamic control functions in order to be able to drive an analogue,  
as well as a digital recording, up to the limit of its maximum dynamic range while remaining noise- and  
distortion-free.  
6.1.1 The MULTICOM PRO In Digital Recording And Sampling  
In an analogue recording, too low recording levels lead to an increased noise level, whereas too high levels will  
cause a compressed and “squashed” sound. In extreme cases, it will cause distortion due to tape saturation.  
In contrast to analogue, side effects in the digital field always become extremely audible: with decreasing level,  
a tape previously recorded with insufficient level loses resolution: the recording sounds “hard“ and loses  
“atmosphere”. With excessive level, the recording sounds harsh and heavily distorted. In order to avoid these  
effects, the Peak Limiter section of the MULTICOM PRO should be placed before for example a sampler. As a  
result of this process, a digital recording or a sampling event can be optimally set in level without any problem.  
6.1.2 The MULTICOM PRO In Mastering  
The mastering process is one of the most critical processing steps in recording. In this production step, it is  
the goal to achieve a “maximum level” copy of the recording, without any noise or distortion. In many  
applications it is further required to produce a high average volume. In the field of commercial media for exam-  
ple, this is apparent especially with records and cassettes which are processed with high average volumes.  
Quite often in these cases, dynamics suffer drastically, because the program material has been compressed  
and limited too heavily. Using the compressor and the Peak Limiter section of the MULTICOM PRO allows you  
to drastically increase the overall volume, without audibly affecting the dynamics.  
Proceed as follows:  
1. Limit the dynamics of the program material by 6 dB using the Peak Limiter section. By softly clipping just  
the transients, the real audio signal will not be limited, resulting in a higher headroom. The overall gain can  
now be increased by 6 dB, which leads to a higher volume. More than 6 dB should not be limited, otherwise  
side effects could become audible.  
2. Therefore, in addition, you should also use compression. It is recommended that the compression is limited  
to the “first” 6 dB of the dynamic range only. A high threshold level in addition to the auto mode will give good  
results.  
This effect is particularly noticeable with DAT recorders, whose level indicators achieve a response time of less  
than 1 ms. Set the DAT recorder at unity and now reduce the LEVEL control of the peak limiter until the LIM  
LED starts to illuminate. The “cut” signal peaks cause a reduced recording level of about 6 dB, which is visible  
on the level indicators of the DAT recorder. Now increase the recording level of the recorder back to unity. The  
result is a clearly louder recording without any loss of sound.  
6.2 The MULTICOM PRO as a protective device  
Sound system distortion is usually a result of amplifiers and loudspeakers being driven beyond their limitations  
by signals clipping. The signal limitations that occur lead to unpleasant distortion that is dangerous to the speakers.  
20  
6. SPECIAL APPLICATIONS  
 
MULTICOM PRO MDX4400  
A speaker diaphragm is required to accelerate, slow down, smoothly change direction and accelerate again in  
normal operation. Distorted operation (clipping) leads to instant acceleration, instant stop, change of direction  
and instant acceleration again. Since speaker diaphragms are subject to the laws of physics, they will not take  
this kind of punishment for long: the diaphragm will either break up or its voice coil may overheat.  
In addition to the damage caused by sustained overload, the speaker may also be damaged by an occasional  
high level overload, e.g. the sound of a microphone falling onto a hard floor. Even if this type of transient does  
not destroy a speaker outright, it may damage the speaker surround in such a way, as to cause mechanical  
abrasion and future failure. It is recommended that you use the BEHRINGER MULTICOM PRO in order to  
protect the speaker. “Brick Wall” peak limiters are not normally necessary for PA systems, as amplifiers and  
loudspeakers are tolerant of short signal peaks.  
Nevertheless, conventional limiters have to be generally driven far beyond the headroom limit of an amplifier, in  
order to limit the level and length of the transients responsible for overloading the system. The disadvantage of  
this principle is that the unit’s full range cannot be completely used. If an increase in the average level of up to  
3 dB is attained with the MULTICOM PROs IGC Peak Limiter, this means that you effectively double the power  
amplification. The MULTICOM PRO can act in this way to convert a PA system of 5,000 Watts into a distortion  
free 10,000 Watts system. The following instructions will help you to integrate the unit into your system.  
6.2.1 Protection Of A System With A Passive Crossover  
If your sound system incorporates a passive crossover network (included in the loudspeaker case), insert the  
BEHRINGER MULTICOM PRO between your mixing console output and the power amplifier input. It is used as  
the last link in the chain preceding the power amp. Thus, you can effectively avoid the “technical knockout” of  
the midrange/tweeter range caused by high-energy bass signals! This statement, as paradox as it may seem  
at first, can be explained with the fact that especially low-frequency signals with high amplitudes can overload  
the power supplies in the amplifier(s). The resulting clipping (cutting off of signal peaks) produces high-energy  
distortion (upper harmonics), which is abruptly added to the midrange/tweeter signals. For this reason, “weak”  
power amps, in particular, must be protected by a limiter in their “input dynamics”.  
6.2.2 Protection Of A System With An Active Crossover  
For systems using active crossovers, there are two ways to use the BEHRINGER MULTICOM PRO. The unit  
may be inserted between the console output and the crossover input. In this application, the BEHRINGER  
MULTICOM PRO will process the entire audio frequency spectrum.  
Alternately, the MULTICOM PRO can be inserted between the output of an active crossover and the input of a  
power amplifier. In this application it will only affect a specific range of frequencies. This application is  
particularly suited to protect the most fragile components of a multi-way speaker system against harmful  
signal peaks. For example, when your tweeters keep on going up in smoke all the time, the entire system  
should be operated at lower sound pressure levels or the tweeters should be replaced by other models. Using  
the MULTICOM PRO in the corresponding tweeter band avoids overloading and thus damage to the speakers.  
6.2.3 Improving The Sound Of A Processor System  
A processor system is understood as a PA system which contains a special active crossover whose outputs  
are linked via separated power amplifiers to the loudspeakers. Each band has its own limiter whose task it is  
to limit dangerous signal peaks to a certain level. This process avoids overloading the subsequent power  
amplifier or destruction of the loudspeaker.  
In some units, the crossover frequencies in the crossover unit are further changed during high signal levels to  
achieve a “loudness contour” suited to the human hearing. But in many cases, this function leads more to a  
disturbance than to an improvement of the sound quality.  
If the MULTICOM PRO is preceding this system, the signal peaks can be eliminated before they reach the  
limiters of the processing system. The sound quality therefore remains natural and free of side effects caused  
by the changing frequencies of the crossover.  
6. SPECIAL APPLICATIONS  
21  
 
MULTICOM PRO MDX4400  
6.3The MULTICOM PRO In Broadcast  
The main aim of processing sound recordings for commercial radio and television is to achieve a maximum  
transmission volume at all costs. Owners of these radio and television stations strive to get bigger audience  
ratings, because principally, radio programs whose reception is louder than the average are preferred by the  
listener. By achieving a bigger audience, the broadcast station gains more money from the increasing number  
of promotion companies placing adverts.  
What is volume?  
Volume is defined as the relationship between the average level of program material to peak-to-peak level, in  
response to amplitude and duration. The higher the average level and the time it remains at a high level, the  
louder the program material will be perceived by the listener.  
If you want to run your broadcast station at maximum average volume, proceed as mentioned in chapter 6.1.2  
“The MULTICOM PRO In Mastering”. Please make sure that the maximum peak level is below the threshold of  
the transmitter’s limiter, otherwise this could lead to very hard and audible use of the transmisson limiters.  
Keep in mind that a heavy increase in average volume by means of compression always leads to a loss in  
dynamics and an increased perception of side effects. The moderate use of the compressor and the Peak  
Limiter sections of the MULTICOM PRO result in higher average volumes, free of distortion.  
22  
6. SPECIAL APPLICATIONS  
 
MULTICOM PRO MDX4400  
7. SPECIFICATIONS  
AUDIO INPUT  
Connectors  
XLR and 1/4" jack  
Type  
Impedance  
Nominal Operating Level  
Max. Input Level  
CMRR  
RF filtered, servo-balanced input  
50 kOhm balanced, 25 kOhm unbalanced  
+4 dBu/-10 dBV switchable  
+21 dBu balanced and unbalanced  
typ. 40 dB, >55 dB @ 1 kHz  
AUDIO OUTPUT  
Connectors  
Type  
XLR and 1/4" jack  
Electronically servo-balanced output stage  
(optional transformer-balanced).  
Impedance  
Max. Output Level  
60 Ohms balanced, 30 Ohm unbalanced  
+21 dBu, +20 dBm balanced and unbalanced  
SYSTEM SPECIFICATIONS  
Bandwidth  
20 Hz to 20 kHz, +0/-0.5 dB  
Frequency Response  
Noise  
0.35 Hz to 200 kHz, +0/-3 dB  
>-95 dBu, unweighted, 22 Hz to 22 kHz  
THD0.008  
%
typ.  
@
0.04 % typ. @ +20 dBu, 1 kHz, Gain 1  
IMD0.01  
%
typ.  
SMPTE  
Crosstalk  
Stereo Coupling  
<-100 dB, 22 Hz to 22 kHz  
True RMS detection  
COMPRESSOR SECTION  
Type  
IKA (Interactive Knee Adaptation) Compressor  
variable (-40 dB to +20 dB)  
Threshold  
Ratio  
variable (1:1 to oo:1)  
Threshold characteristics  
Auto characteristics  
Auto Attack Time  
Auto Release Time  
Output  
variable (Interactive or Hard Knee)  
Wave Adaptive Compressor  
typ. 15 ms at 10 dB, 5 ms at 20 dB, 3 ms at 30 dB  
program dependent, typ. 125 dB/s  
variable (-20 to +20 dB)  
PEAK LIMITER SECTION  
Type  
IGC (Interactive Gain Control) Peak Limiter  
Threshold  
variable (+4 dB to OFF (+22 dBu))  
Ratio  
oo:1  
Stage 1 Limiter Type  
Attack  
Clipper  
“zero”  
Release  
“zero”  
Stage 2 Limiter Type  
Attack  
Release  
Program Limiter  
program dependent, typ. < 5 ms  
program dependent, typ. 20 dB/s  
FUNCTION SWITCHES  
INTERACTIVE  
CONTOUR  
Enables the “Interactive KneeAdaptation” characteristics.  
Allows for frequency dependent detection.  
Switches between input and output for the Level Meter.  
Bypass switch.  
I/O METER  
IN/OUT  
OPERATING LEVEL  
COUPLE  
Changes the internal reference level from +4 dBu to -10 dBV.  
Linking channels 1&2 or 3&4 for stereo operation. Channel 1 (or 3)  
becomes master.  
7. SPECIFICATIONS  
23  
 
MULTICOM PRO MDX4400  
INDICATORS  
GAIN REDUCTION  
8 element LED display: 1/3/6/10/15/20/25/30 dB  
8 element LED display: -24/-18/-12/-6/0/+6/+12/+18 dB  
1 LED for Indication of Limiter function  
LED indicator for each  
INPUT/OUTPUT LEVEL  
Peak Limiter Threshold  
Function switch  
POWER SUPPLY  
Mains Voltages  
USA/Canada  
U.K./Australia  
Europe  
120 V ~, 60 Hz  
240 V ~, 50 Hz  
230 V ~, 50 Hz  
General Export Model  
100 - 120 V ~, 200 - 240 V ~, 50 - 60 Hz  
Fuse  
100 - 120 V ~: T 630 mA H  
200 - 240 V ~: T 315 mA H  
max. 32 W  
Power Consumption  
Mains Connection  
Standard IEC receptacle  
PHYSICAL  
Dimension  
1 3/4" (44.5 mm) * 19" (482.6 mm) * 8 1/2" (217 mm)  
Net Weight  
Shipping Weight  
2.2 kg  
3.4 kg  
BEHRINGER is constantly striving to maintain the highest professional standards. As a result of these efforts, modifications may be  
made from time to time to existing products without prior notice. Specifications and appearance may differ from those listed or illustrated.  
24  
7. SPECIFICATIONS  
 
MULTICOM PRO MDX4400  
8. WARRANTY  
§ 1 WARRANTY CARD/ONLINE REGISTRATION  
To be protected by the extended warranty, the buyer must com-  
plete and return the enclosed warranty card within 14 days of  
the date of purchase to BEHRINGER Spezielle Studiotechnik  
GmbH, in accordance with the conditions stipulated in § 3. Fail-  
ure to return the card in due time (date as per postmark) will void  
any extended warranty claims.  
3. Free inspections and maintenance/repair work are expressly  
excluded from this warranty, in particular, if caused by improper  
handling of the product by the user.  
This also applies to defects caused by normal wear and tear, in  
particular, of faders, potentiometers, keys/buttons and similar  
parts.  
Based on the conditions herein, the buyer may also choose to  
use the online registration option via the Internet  
4. Damages/defects caused by the following conditions are not  
covered by this warranty:  
s misuse, neglect or failure to operate the unit in compliance  
with the instructions given in BEHRINGER user or service  
manuals.  
§ 2 WARRANTY  
1. BEHRINGER (BEHRINGER Spezielle Studiotechnik GmbH in-  
cluding all BEHRINGER subsidiaries listed on the enclosed page,  
except BEHRINGER Japan) warrants the mechanical and elec-  
tronic components of this product to be free of defects in mate-  
rial and workmanship for a period of one (1) year from the  
original date of purchase, in accordance with the warranty regu-  
lations described below. If the product shows any defects within  
the specified warranty period that are not due to normal wear  
and tear and/or improper handling by the user, BEHRINGER shall,  
at its sole discretion, either repair or replace the product.  
s connection or operation of the unit in any way that does not  
comply with the technical or safety regulations applicable in  
the country where the product is used.  
s damages/defects caused by force majeure or any other  
condition that is beyond the control of BEHRINGER.  
5. Any repair or opening of the unit carried out by unauthorized  
personnel (user included) will void the warranty.  
6. If an inspection of the product by BEHRINGER shows that the  
defect in question is not covered by the warranty, the inspection  
costs are payable by the customer.  
2. If the warranty claim proves to be justified, the product will be  
returned to the user freight prepaid.  
3. Warranty claims other than those indicated above are ex-  
pressly excluded.  
7. Products which do not meet the terms of this warranty will be  
repaired exclusively at the buyer’s expense. BEHRINGER will  
inform the buyer of any such circumstance. If the buyer fails to  
submit a written repair order within 6 weeks after notification,  
BEHRINGER will return the unit C.O.D. with a separate invoice  
for freight and packing. Such costs will also be invoiced sepa-  
rately when the buyer has sent in a written repair order.  
§ 3 RETURN AUTHORIZATION NUMBER  
1. To obtain warranty service, the buyer (or his authorized dealer)  
must call BEHRINGER (see enclosed list) during normal business  
hours BEFORE returning the product. All inquiries must be ac-  
companied by a description of the problem. BEHRINGER will then  
issue a return authorization number.  
§ 5 WARRANTY TRANSFERABILITY  
2. Subsequently, the product must be returned in its original  
shipping carton, together with the return authorization number to  
the address indicated by BEHRINGER.  
This warranty is extended exclusively to the original buyer (cus-  
tomer of retail dealer) and is not transferable to anyone who  
may subsequently purchase this product. No other person (re-  
tail dealer, etc.) shall be entitled to give any warranty promise on  
behalf of BEHRINGER.  
3. Shipments without freight prepaid will not be accepted.  
§ 4 WARRANTY REGULATIONS  
§ 6 CLAIM FOR DAMAGES  
1. Warranty services will be furnished only if the product is  
accompanied by a copy of the original retail dealer’s invoice.  
Any product deemed eligible for repair or replacement by  
BEHRINGER under the terms of this warranty will be repaired or  
replaced within 30 days of receipt of the product at BEHRINGER.  
Failure of BEHRINGER to provide proper warranty service shall  
not entitle the buyer to claim (consequential) damages. In no  
event shall the liability of BEHRINGER exceed the invoiced value  
of the product.  
§ 7 OTHER WARRANTY RIGHTS AND NATIONAL LAW  
2. If the product needs to be modified or adapted in order to  
comply with applicable technical or safety standards on a na-  
tional or local level, in any country which is not the country for  
which the product was originally developed and manufactured,  
this modification/adaptation shall not be considered a defect in  
materials or workmanship. The warranty does not cover any  
such modification/adaptation, irrespective of whether it was  
carried out properly or not. Under the terms of this warranty,  
BEHRINGER shall not be held responsible for any cost resulting  
from such a modification/adaptation.  
1. This warranty does not exclude or limit the buyer’s statutory  
rights provided by national law, in particular, any such rights  
against the seller that arise from a legally effective purchase  
contract.  
2. The warranty regulations mentioned herein are applicable  
unless they constitute an infringement of national warranty law.  
The information contained in this manual is subject to change without notice. No part of this manual may be reproduced or  
transmitted in any form or by any means, electronic or mechanical, including photocopying and recording of any kind, for any  
purpose, without the express written permission of BEHRINGER Spezielle Studiotechnik GmbH.  
BEHRINGER and MULITCOM are registered trademarks.  
ALLRIGHTS RESERVED. © 2001 BEHRINGER Spezielle Studiotechnik GmbH.  
BEHRINGER Spezielle Studiotechnik GmbH, Hanns-Martin-Schleyer-Str. 36-38, 47877 Willich-Münchheide II, Germany  
Tel. +49 (0) 21 54 / 92 06-0, Fax +49 (0) 21 54 / 92 06-30  
8. WARRANTY  
25  
 

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