Version 1.3 April 2001 ® www.behringer.
MULTICOM PRO MDX4400 SAFETY INSTRUCTIONS CAUTION: To reduce the risk of electric shock, do not remove the cover (or back). No user serviceable parts inside; refer servicing to qualified personnel. WARNING: To reduce the risk of fire or electric shock, do not expose this appliance to rain or moisture. This symbol, wherever it appears, alerts you to the presence of uninsulated dangerous voltage inside the enclosurevoltage that may be sufficient to constitute a risk of shock.
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.
MULTICOM PRO MDX4400 MULTICOM PRO ® Interactive 4-channel compressor/limiter/peak limiter of the reference class soft knee characteristics MDX4400 s IKA (Interactive Knee Adaptation) compressor concept combines the advantages of hard knee and s Switchable highpass filter in control signal path avoids low-frequency signals from dominating compressor action s Compression characteristics switchable between IKA and hard knee characteristics s IGC (Interactive Gain Control) peak limiter combines cl
MULTICOM PRO MDX4400 TABLE OF CONTENT 1. INTRODUCTION .....................................................................................................................6 1.1 Technical Background ..................................................................................................................... 1.1.1 Noise As A Physical Phenomenon ........................................................................................ 1.1.2 What Are Audio Dynamics? ......................................
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.
MULTICOM PRO MDX4400 overall output signal so that no audible distortion occurs (program limiter). After the level falls below the threshold, 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.
MULTICOM PRO MDX4400 P/dB 140 120 Cassette Recorder Radio Ear 40 Tape Recorder 60 Power Amplifier 80 Microphone Amplifier 100 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.
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.
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.
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.
MULTICOM PRO MDX4400 Unbalanced use of mono 1/4" jack plugs Balanced use of stereo 1/4" jack plugs Tip = Signal Tip = hot (+ve) Ring = cold (-ve) Sleeve = Ground / Shield Sleeve = Ground / Shield Tip Tip Sleeve Ring 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.
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 pushbuttons, 4 rotary controls and 17 LEDs. The COUPLE switches are for stereo operation of two channels. 4.1 The Front Panel Control Elements 7 11 1 6 8 2 5 3 10 4 9 Fig. 4.2: Control elements on the front panel 1 The THRESHOLD control sets the threshold point for the compressor section. It has a range of -40 to +20 dB.
MULTICOM PRO MDX4400 7 The 8-digit GAIN REDUCTION meter indicates how effectively the gain is reduced by the compressor, within a range from 1 to 30 dB. 8 The 8-digit INPUT/OUTPUT LEVEL meter informs youdepending on the setting of the I/O METER switchabout 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.
MULTICOM PRO MDX4400 4.4 Rear Panel Control Elements Of The MULTICOM PRO 12 16 13 15 14 Fig. 4.5: Control elements of the rear panel 12 FUSE HOLDER / VOLTAGE SELECTOR. Please make sure that your local voltage matches the voltage 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 MAINS CONNECTION. Use the enclosed power cord to connect the unit to the mains.
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 capabilities in the future.
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.
MULTICOM PRO MDX4400 5.2.1 Initial Settings For The Compressor Section C ontrol Setti ng IN/OUT swi tch IN INTERAC TIVE swi tch IN SC FILTER swi tch OUT THRESHOLD control +20 dB RATIO control 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.
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.
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.
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.
MULTICOM PRO MDX4400 6.3 The 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.
MULTICOM PRO MDX4400 7. SPECIFICATIONS AUDIO INPUT Connectors Type Impedance Nominal Operating Level Max. Input Level CMRR AUDIO OUTPUT Connectors Type Impedance Max. Output Level SYSTEM SPECIFICATIONS Bandwidth Frequency Response Noise THD IMD Crosstalk Stereo Coupling XLR and 1/4" jack RF filtered, servo-balanced input 50 kOhm balanced, 25 kOhm unbalanced +4 dBu/-10 dBV switchable +21 dBu balanced and unbalanced typ.
MULTICOM PRO MDX4400 INDICATORS GAIN REDUCTION INPUT/OUTPUT LEVEL Peak Limiter Threshold Function switch POWER SUPPLY Mains Voltages Fuse Power Consumption Mains Connection PHYSICAL Dimension Net Weight Shipping Weight 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 USA/Canada 120 V ~, 60 Hz U.K.
MULTICOM PRO MDX4400 8. WARRANTY § 1 WARRANTY CARD/ONLINE REGISTRATION To be protected by the extended warranty, the buyer must complete 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. Failure to return the card in due time (date as per postmark) will void any extended warranty claims.
