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Dual 31 Band
Graphic Equaliser &
Dynamics Processor
User Manual
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User Manual Copyright Copyright Copyright 2004. All rights reserved. The information in this document is subject to change without notice. Audient plc makes no warranty of any kind with respect to the material in this document and shall not be liable for errors contained herein or for incidental or consequential damages related to the use of the material. No part of this document may be reproduced without the prior written consent of Audient plc. ©
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User Manual Thank you Thank you for buying this product. As can be found throughout the LA Audio range, your EQ231G-SP has been designed and manufactured to the highest possible standards of performance and reliability. To make the most of your unit, we suggest that you take some time to acquaint yourself with the contents of this manual before you get started. The safety and installation information will help you set up your EQ231G-SP with the minimum of effort, while the operation
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User Manual Contents Contents IMPORTANT SAFETY INSTRUCTIONS 5 Safety Information 6 1. Introduction 7 2. Installation 8 3. Operating Instructions 11 4. Applications & Techniques 13 5. Block Diagram & Specifications 17 6. Repairs and Warranty 19 © LA Audio 2004 4
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User Manual IMPORTANT SAFETY INSTRUCTIONS IMPORTANT SAFETY INSTRUCTIONS CAUTION ATTENTION RISK OF ELECTRIC SHOCK RISQUE DE CHOC DO NOT OPEN DO NOT OPEN DO NOT OPEN DO NOT OPEN NE PAS ENLEVER NE PAS ENLEVER NE PAS ENLEVER NE PAS ENLEVER WARNING THIS EQUIPMENT MUST BE EARTHED. DO NOT EXPOSE TO RAIN OR MOISTURE. PLEASE READ ALL OF THE FOLLOWING INSTRUCTIONS AND SAVE THEM FOR LATER REFERENCE BEFORE ATTEMPTING TO CONNECT YOUR UNIT TO THE AC PO
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User Manual Safety Information Safety Information EARTH This unit is connected via its power cord to the mains safety earth. NEVER OPERATE THE UNIT WITH THIS EARTH CONNECTION REMOVED. COVERS DO NOT remove the covers. Refer servicing to qualified personnel only. VOLTAGE The EQ231G-SP is set to operate only at the voltage shown on the outer packaging. CHECK that the correct voltage is available before connecting the AC mains supply. FUSES CHECK that the fuse fitted is of the
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User Manual 1. Introduction 1. Introduction The EQ231G-SP is a high quality dual 31-band 1/3 octave graphic equaliser including variable Hi and Lo-pass filters, Shelving EQ, Gate and Limiter. The Graphic Equaliser features centre detented, 45mm faders which give up to 12dB of cut and boost at 31 ISO centre frequencies, covering the entire audio spectrum (20 to 20KHz). The Hi-pass filter uses 4th order bi-quadratic topology giving a 24 dB/octave slope with corner frequency varia
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User Manual 2. Installation 2. Installation It is important to read this section before applying power to the unit. 2.1. Inspection and unpacking The EQ231G-SP is carefully packed at the factory in a carton which is designed to withstand handling in transit. However if transit damage is evident, DO NOT discard any of the packaging material and notify the carrier and your dealer immediately. The shipment should contain the following: • The Unit, EQ231G-SP Graphic Equaliser • Po
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User Manual 2. Installation (contd.) 2.4. External connections The input and output connectors are wired on female and male XLRs respectively, wired as follows: Pin 1: Ground Pin 2: Hot balanced signal Pin 3: Cold balanced signal 2.5. Impedance & Termination Most modern audio systems have cable runs of less than 100 meters; the devices used usually have very low output impedance and relatively high input impedance. This allows equipment to be connected in series without
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User Manual 2. Installation (contd.) 2.6. Signal levels The unit is designed to accept an input signal level of up to +20dBu (dB referred to 0.775Vrms). Above this, clipping (distortion) of the signal will occur. It should be noted that the filter amplifiers may be driven into distortion by excessive boost in the unit, and where this is the case the input signal should be reduced sufficiently to allow enough headroom. © LA Audio 2004 10
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User Manual 3. Operating Instructions 3. Operating Instructions 3.1. Controls 1. EQ faders allow high-resolution control over EQ gain at 31 ISO frequencies. The frequency is indicated on the front panel, as are the amounts of cut and boost, between 12 and +12 dB. Each fader has a centre detent, which allows you to quickly return it to its inactive (0dB) position. 2. Graphics ON switch allows the graphic filters to be taken out of circuit for comparison checks. The adjacen
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User Manual 3. Operating Instructions (contd.) 5. Shelving Filter Bypass switch allows the filter to be taken out of circuit. This allows you to hear its effects when compared to the unfiltered sound, and also to allow low frequencies to pass unaffected. 6. Shelving Filter Frequency rotary potentiometers enable control of the LF and HF shelf frequency. 7. Shelving EQ section faders enable control of the amount of cut or boost, a centre detent is provided at 0dB. 8. The Hig
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User Manual 3. Operating Instructions (contd.) © LA Audio 2004 13
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User Manual 4. Applications & Techniques 4. Applications & Techniques A graphic equaliser may be used in numerous situations, in many different ways. It is impossible to document every implementation, but we hope that the following examples will serve as a useful starting point. 4.1. Some Examples a) Room equalisation Every room, whether it be in a studio, theatre or home has a different acoustic response, depending upon room dimensions, fixtures and fittings and any other abso
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User Manual 4. Applications & Techniques (contd.) technique is quite common in recording or production studios to tailor a sound for its eventual reproduction medium. c) Elimination of "sibilance" Sibilance is the noise which occurs when someone is speaking who either has a "hissy" voice or who is using words with the letter s in them, e.g. sibilance. This can become annoying to a listener and the graphic equaliser can be used to overcome this problem by either removing or reducing
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User Manual 4. Applications & Techniques (contd.) Another useful effect that can be created with a graphic EQ is a Comb Over. To give a mono source some interest in a stereo mix, the graphic equaliser can be used to create variances in each side of the stereo signal, thereby widening the sound. Route the mono signal to both channels of the EQ231G-SP and on each channel cut alternate frequencies by around 6dB. With certain source material, you may need to cut less at low frequencies to a
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User Manual 4. Applications & Techniques (contd.) compressor or limiter. Placing the graphic equaliser after dynamics could cause the compressor or limiter to react to frequencies not audible in the output, creating unusual undulations in volume not associated with the program material. The second reason for placing the graphic equaliser before dynamics occurs where the dynamics processor is being used to safeguard PA systems or digital recorders. As the equaliser can create changes in
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User Manual 5. Block Diagram & Specifications 5. Block Diagram & Specifications 5.1 Block Diagram © LA Audio 2004 18
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User Manual 5. Block Diagram & Specifications (contd.) 5.2 Specifications Frequency Response 20 Hz - 20 kHz, -1dB Signal to Noise Ratio @ +4dBu output -96dB Input impedance 20 kΩ balanced Output impedance 100Ω balanced Maximum Output Level +20dBu (into 600Ω Load, 1 kHz, 600 Ohms Load) Total Harmonic Distortion 0.003 % (1kHz, +4dBu Output) Peak indicator Threshold 2dB before clipping Centre frequencies : 20, 25, 31.5, 40, 50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500,
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User Manual 6. Repairs and warranty 6. Repairs and warranty The EQ231G-SP is a ruggedly constructed solid-state unit that requires no preventative or routine maintenance. The unit is constructed from the highest quality components, which are selected to provide consistent, long-lasting performance. Each unit is soak-tested before despatch sifting out any rogue components before they leave the factory. If correctly installed and operated the unit should give years of problem fre
