Allen&Heath GR8A User Manual

GR8A

8 Channel Amplifier

USER GUIDE

Publication AP4298

Limited One Year Warranty

This product has been manufactured in the UK by ALLEN & HEATH and is warranted to be free from defects in materials or workmanship for a period of one year from the date of purchase by the original owner.

To ensure a high level of performance and reliability for which this equipment has been designed and manufactured, read this User Guide before operating.

In the event of a failure, notify and return the defective unit to ALLEN & HEATH or its authorised agent as soon as possible for repair under warranty subject to the following conditions

Conditions Of Warranty

The equipment has been installed and operated in accordance with the instructions in this User Guide

The equipment has not been subject to misuse either intended or accidental, neglect, or alteration other than as described in the User Guide or Service Manual, or approved by ALLEN & HEATH.

Any necessary adjustment, alteration or repair has been carried out by ALLEN & HEATH or its authorised agent.

The defective unit is to be returned carriage prepaid to ALLEN & HEATH or its authorised agent with proof of purchase.

Units returned should be packed to avoid transit damage.

In certain territories the terms may vary. Check with your ALLEN & HEATH agent for any additional warranty which may apply.

This product complies with the European Electromagnetic Compatibility directives 89/336/EEC & 92/31/EEC and the European Low Voltage Directives 73/23/EEC & 93/68/EEC.

Any changes or modifications to the equipment not approved by Allen & Heath could void the compliance of the equipment and therefore the users authority to operate it.

GR8A User Guide AP4298 Issue 2.

Manufactured in the United Kingdom by

Allen & Heath Limited Kernick Industrial Estate, Penryn, Cornwall, TR10 9LU, UK

http://www.allen-heath.com

2 GR8A USER GUIDE

CONTENTS

Warranty............................................................................... 2

Safety Warnings................................................................... 3

Welcome to the Allen & Heath GR8A .................................. 4

General Precautions ............................................................ 4

Specifications....................................................................... 5

Front Panel Controls ............................................................ 6

Rear Panel Controls and Connectors .................................. 7

Installation............................................................................ 9

Operation ........................................................................... 10

Block Diagram.................................................................... 11

SAFETY WARNING!

Mains electricity is dangerous and can kill. Mains voltage is present within the GR8A.

Do not remove the top cover. There are no user serviceable parts inside the unit. Refer servicing to qualified service personnel only.

To avoid the risk of fire, replace the mains fuse only with the correct value and type as indicated on the rear panel.

WARNING TO THE USER, INSTALLATION ENGINEER

Allen & Heath warns that any unauthorised changes or modifications to the GR8A unit may invalidate the legal compliance of the unit and could void the user’s authority to operate the equipment.

DO NOT REMOVE THE MAINS EARTH CONNECTION

To ensure your safety the mains earth is connected to the chassis through the power lead. Do not remove this connection.

GR8A USER GUIDE 3

Welcome to the Allen & Heath GR8A

The GR8A is one of a range of architectural sound products in the Allen & Heath Contractor Series. It is an 8 channel audio power amplifier designed to work with multi-output zoning mixers such as the Allen & Heath GR05, GR1, DR128 and DR66. Modern amplifier technology has enabled the GR8A to achieve multi-channel high power output in a relatively small case size. Much time and effort has been invested into making the GR8A an excellent performing, reliable and cost effective solution wherever multi-channel audio is required. The GR8X transformer rack option is available from Allen & Heath to enable the amplifier to drive 70V or 100V loudspeaker systems.

This user guide presents a quick reference to the function and application of the GR8A. We recommend that you read this guide fully before starting. Whilst we believe the information presented to be reliable, we do not assume responsibility for inaccuracies. We also reserve the right to make changes in the interest of further product development.

Main Features

• 8 Independent audio power amplifiers in a 2U chassis with removable rack ears

• 60W per channel into 4 ohms, 40W into 8 ohms

• Outputs bridgeable for 120W into 8 ohms

• Balanced XLR inputs with common mono/stereo source switching in groups of four

• Speaker outputs on Phoenix type removable screw terminal connectors

• 3 Colour input signal metering

• Selectable output monitoring on headphones or local speaker

• Full output protection and 3 speed fan cooled temperature management system

• Battery power backup facility

• Remote output ‘standby’ control per channel

Service And Technical Support

Under normal operating conditions the GR8A does not require user maintenance or calibration apart from occasional vacuuming of the air intake filter should it become ingrained with dust.

To avoid damage to internal components by mishandling and/or misconnection, service

work should be referred only to technically competent personnel.

We are able to offer further product support through our world-wide network of approved dealers and service agents. You can also access our Web site on the internet for information on our product range, assistance with your technical queries or simply to chat about audio matters. To help us provide the most efficient service please keep a record of the serial number, date and place of purchase to be quoted in any communication regarding this product.

General Precautions

Your GR8A is ruggedly constructed to give many years of reliable operation. However, you will extend the life of the amplifier and preserve its cosmetics by applying these simple common sense precautions:

Avoid storing or using the amplifier in conditions of excessive heat or cold, or in positions where it is likely to be subject to vibration, dust, smoke, dirt or moisture. Do not use any liquids to clean the control surface of the unit. Use a soft dry brush or dry lint-free cloth. Check the air intake dust filter regularly and vacuum from the outside to remove dust build up as necessary. Avoid using the amplifier close to strong sources of electromagnetic radiation such as video monitors, mains and high power electric cabling.

Do not remove the service cover. There are no user serviceable parts inside. All the controls and installation settings for the unit are accessible from the outside.

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