April 2001 www.behringer.com E ENGLISH XR4400 Version 1.
MULTIGATE PRO XR4400 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.
MULTIGATE PRO XR4400 FOREWORD Dear Customer, Welcome to the team of MULTIGATE 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.
MULTIGATE PRO XR4400 MULTIGATE PRO ® Audio interactive 4-channel expander/gate of the high-end class s UTR (Ultra Transient Response) selectable ultra-fast gate s IRC (Interactive Ratio Control) selectable ultra-smooth expander s Fully adjustable ratio control in expander mode s Fully adjustable attenuation control in gate mode s Independent hold/release controls for any envelope shaping s FlexLink system for flexible master/slave configurations s Filter monitor facility for monitoring the filter section
MULTIGATE PRO XR4400 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? ....................................
MULTIGATE PRO XR4400 1. INTRODUCTION With the BEHRINGER MULTIGATE PRO you purchased a dynamics processor of the high-end class designed to meet highest requirements: professional recording, broadcast and television studios, CD and digital production facilities, etc.
MULTIGATE PRO XR4400 + The following operational manual will introduce you to the BEHRINGER MULTIGATE PRO and its various functions. After reading the manual carefully, make sure it is always on hand for future reference. 1.1 Technical background By employing current modern analog technology it is possible to manufacture audio equipment with a dynamic range of up to 130 dB. In contrast to analog techniques, the dynamic range of digital equipment is approximately 25 dB less.
MULTIGATE PRO XR4400 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.
MULTIGATE PRO XR4400 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.
MULTIGATE PRO XR4400 For the first time, the MULTIGATE PRO XR4400 uses SMD technology (Surface Mounted Device). These sub-miniature components known from aerospace technology allow for an extreme packing density, plus the units reliability could be improved. Additionally, the unit is manufactured in compliance with a ISO9000 certified management system. 2.2 Inputs and outputs 2.2.
MULTIGATE PRO XR4400 Output Cable Input Ground Pin 1 2 1 1 Shield (+) Signal + Hum (-) Signal + Hum Pin 2 = (+) Signal 3 2 Positive (+)Hum + Signal Negative (-)Hum + Signal 3 Pin 3 = (-) Signal 2 x Signal = Signal + 6 dB RFI and Hum Fig. 3.
MULTIGATE PRO XR4400 4. CONTROLS Fig. 4.1: MULTIGATE PRO front panel The BEHRINGER MULTIGATE PRO has four channels. Each of these channels is equipped with 3 or 4 pushbuttons, 6 rotary controls and 11 LEDs. 4.1 The front panel control elements Fig. 4.2: Control elements on the front panel 1 The FREQUENCY control determines the lower limit frequency of the sidechain filter, and covers a range from 100 Hz to 10 kHz. 2 The BANDWIDTH control determines the slope or bandwidth of the sidechain filter.
MULTIGATE PRO XR4400 6 This traffic light LED chain shows the current operating mode of the unit: the + LED (red) indicates that the sidechain signal is below the threshold, the HOLD LED (yellow) informs you that the hold circuit/release process has been activated, while the - LED (green) shows that the sidechain signal is above the threshold. 7 The HOLD control determines the delay applied to the starting point of the release process, after the signal has dropped below the threshold.
MULTIGATE PRO XR4400 5. TECHNICAL BACKGROUND 5.1 EXPANDER mode As already described, a so-called downward expander automatically reduces the overall level of all signals that drop below an adjustable threshold, and thus expands the dynamic range of the program material. In other words, an expander is the opposite of a compressor. Expanders usually work with a relatively flat ratio curve to fade out the signal smoothly.
MULTIGATE PRO XR4400 5.2.2 Attack, release and hold times The BEHRINGER MULTIGATE PRO is equipped with a MODE switch as well as a HOLD and RELEASE control to adjust the time-domain parameters that determine the so-called envelope: Fig. 6.2: Principle of envelope function Attack time The quality of an expander/gate is largely determined by the speed of its attack function (rise time).
MULTIGATE PRO XR4400 gain reduction applied. Thus, you can use smaller amounts of gain reduction making it possible to retain the natural sound of the program materialin particular, with signals that contain plenty of interference noise. 5.2.5 IRC circuit (Interactive Ratio Control) In conventional expanders the control processes cut the signal abruptly below the threshold, which usually leads to less satisfying results, because the onset of the control function becomes audible.
MULTIGATE PRO XR4400 point of time. Also when synchronizing several instruments, inaccurate entries of individual musicians can be avoided. To expand phase-coherent stereo signals (i.e. signals having the same phase), it is imperative that the control processes be triggered simultaneously in both channels. Due to the differences in perceived loudness between the left and right channels, unwanted shifts with reference to the stereo basis would be produced.
MULTIGATE PRO XR4400 multitrack mixdowns, stage microphones currently not in use and to suppress background noise and crosstalk in multi-track recordings. In particular, when processing percussive instrument the use of the hard gating function is recommended. A few examples show you how to do it: Electric signals from percussion instruments have a very short rise time.
MULTIGATE PRO XR4400 signal will not be suppressed completely. Although the MULTIGATE PRO allows for a maximum gain reduction of 80 dB, it is usually not useful to reduce the signal level by this maximum amount. In particular, with highly noise-affected signals we recommend that you use a signal attenuation of not more than 10 to 20 dB, so that the onset of the gate function will not become too obvious. 6.1.
MULTIGATE PRO XR4400 The high sound pressure levels of the individual instruments lead to crosstalk in adjacent microphones. Frequency cancellations and a non-defined sound (comb filter effect) are the result. It has proven wise to use a separate microphone for each drum instrument and to gate each microphone channel. Insert the BEHRINGER MULTIGATE PRO into the recording channel of the snare drum, for example, and adjust the device so that it responds only to hits on the snare drum.
MULTIGATE PRO XR4400 7. SPECIFICATIONS AUDIO INPUT Connectors Type Impedance Max. Input Level CMRR XLR and 1/4" jack RF filtered, servo-balanced input 50 kOhm balanced, 25 kOhm unbalanced +21 dBu balanced and unbalanced typ. 40 dB, >55 dB @ 1 kHz AUDIO OUTPUT Connectors Type Impedance Max.
MULTIGATE PRO XR4400 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.
