Benchmark MPA1 Manuel d'instructions

Benchmark PRE420 Instruction Manual 4-Channel Microphone Preamplifier/Mixer

PRE420 Instruction Manual – rev. E Page 10 current low-capacitance input protection circuits that protect the sensitive low-noise input transistors f

PRE420 Instruction Manual – rev. E Page 11 MirrorPan™ Pan Controls The PRE420 incorporates Benchmark’s new MirrorPan™ constant-power pan control. T

PRE420 Instruction Manual – rev. E Page 12 Solo Bus The PRE420 has a flexible solo bus that allows: • Mono monitoring of any mix of microphones •

PRE420 Instruction Manual – rev. E Page 13 Control Room Outputs The output of the solo bus is directed to the “monitor” fader and then to the headpho

PRE420 Instruction Manual – rev. E Page 14 HPA2™ Headphone Output The output of the solo bus is directed to the “monitor” fader and then to the headp

PRE420 Instruction Manual – rev. E Page 15 Mix Outputs The output of the mix bus is directed to the “Main” fader and then to the “Main” outputs. Ma

PRE420 Instruction Manual – rev. E Page 16 Rack Mounting To enable rack mounting, the front panel of the PRE420 has rack-mount holes that are machine

PRE420 Instruction Manual – rev. E Page 17 Performance Graphs Frequency Response Audio Precision02/19/07 11:33:00PRE420 - Frequency ResponseColorSwe

PRE420 Instruction Manual – rev. E Page 18 High-Pass Filter - Frequency Response Audio Precision02/19/07 11:33:00PRE420 - Frequency ResponseColorSw

PRE420 Instruction Manual – rev. E Page 19 Inter-Channel Phase Response Audio Precision02/19/07 11:35:37PRE420 - Inter-Channel Phase Response-1+1-0.9

Safety Information Voltage Selection CAUTION: THE FUSE DRAWER INCLUDES A VOLTAGE SELECTION SWITCH WITH TWO SETTINGS: “110” AND “220”. CHECK TO SEE THA

PRE420 Instruction Manual – rev. E Page 20 THD+N vs. Frequency Measurement Bandwidth = 10Hz to 80 kHz, Gain = 30 to 60 dB, Output Level = +4 dBu Audi

PRE420 Instruction Manual – rev. E Page 21 Wideband THD+N vs. Frequency Measurement Bandwidth = 10 Hz to 500 kHz, Gain = 30 to 60 dB, Output Level =

PRE420 Instruction Manual – rev. E Page 22 Equivalent Input Noise vs. Gain The above plot shows the Equivalent Input Noise (EIN) of the PRE420 as a

PRE420 Instruction Manual – rev. E Page 23 Noise Spectrum 32k B-H FFT, Gain = 60 dB, 0 dBr = 0 dBu at input Audio Precision02/19/07 11:27:19Noise Spe

PRE420 Instruction Manual – rev. E Page 24 THD Spectrum at 1 KHz Audio Precision02/21/07 09:43:491 kHz FFT at 60 dB Gain, Output Level = +24 dBu, 0 d

PRE420 Instruction Manual – rev. E Page 25 THD Spectrum at 10 KHz Audio Precision02/19/07 11:09:3010 kHz FFT at 60 dB Gain, Output Level = +24 dBu, 0

PRE420 Instruction Manual – rev. E Page 26 Specifications Microphone Preamps Number of Preamps 4 Connectors Gold-Pin Neutrik™ female XLR with dire

PRE420 Instruction Manual – rev. E Page 27 Direct Outputs Number of Outputs 4 Connectors Gold-Pin Neutrik™ male XLR with direct ground feature Out

PRE420 Instruction Manual – rev. E Page 28 MirrorPan™ Constant-Power Pan Circuit Number of pan controls 4 Pan Law 3-dB (constant power to stereo o

PRE420 Instruction Manual – rev. E Page 29 LED Status Indicators and Meters +48V Phantom Indicators 4 Solo Warning Indicator 1 Power Indicator 1

ContentsSafety Information 2 Voltage Selection 2 Repairs 2 Fuses 2 Modifications 2 Contents 3 Overview 4 Features 6 Connections 7 Microphone

PRE420 Instruction Manual – rev. E Page 30 Dimensions Form Factor 19” Rack Mount, 1 RU High Depth behind front panel 11.75” (298.5 mm) Overall dep

PRE420 Instruction Manual – rev. E Page 31 Regulatory Compliance FCC Notice RoHS Compliant Information FCC Notice (U.S. Onl

PRE420 Instruction Manual – rev. E Page 32 CE Certificate of Conformity

PRE420 Instruction Manual – rev. E Page 33 Warranty Information The Benchmark 1 Year Warranty Benchmark Media Systems,

PRE420 Instruction Manual – rev. E Page 34 Benchmark Extended Warranty The Benchmark Extended 5* Year Warranty Benchmark Media Systems, I

PRE420 Instruction Manual – rev. E Page 35 Calibration CAUTION: ROUTINE CALIBRATION SHOULD NOT BE REQUIRED. THE FOLLOWING PROCEDURE SHOULD ONLY BE U

PRE420 Instruction Manual – rev. E Page 36 21. Set audio tone generator to 1 kHz with an output level of -36 dBu (or level used in step 3). 22. Conn

PRE420 Instruction Manual – rev. E Page 37 Copyright © 2007 Benchmark Media Systems, Inc. All rights reserved. Benchmark Media System

PRE420 Instruction Manual – rev. E Page 4 Overview The PRE420 is a 4-channel microphone preamplifier/mixer and is designed to achieve the highest p

PRE420 Instruction Manual – rev. E Page 5 dimensional shield surrounding the microphone-level signal traces to block RF interference. Also, the micro

PRE420 Instruction Manual – rev. E Page 6 Features • Four Transformerless Microphone Inputs • Four Balanced Direct Outputs (XLR) • Balanced Left

PRE420 Instruction Manual – rev. E Page 7 Connections Microphone Inputs (1-4) The balanced transformerless microphone inputs use locking Neutrik™ g

PRE420 Instruction Manual – rev. E Page 8 pin Neutrik™ male XLR connectors with direct chassis bonding of both pin 1 and the connector shell. This d

PRE420 Instruction Manual – rev. E Page 9 Preamp Section Preamp Overview Each preamp channel includes switches for phantom power, a 20 dB pad, and a