Cambridge Audio Azur 840W user manual Contents, Introduction

Contents
Important safety instructions	2
Limited warranty	3
Contents	4
Introduction	4
Rear panel connections	5
Front panel controls	6
Connections	7
Unbalanced stereo connections	7
Balanced stereo connections	7
Power syncing	7
Advanced connections	8
Bi-wired stereo connections	8
Bi-amped dual mono connections	9
Bridged dual mono connections	9
Custom installation use	10
Technical specifications	10
Troubleshooting	11

Visit www.cambridge-audio.com and register to receive notification of future hardware and software releases.

This guide is designed to make installing and using this product as easy as possible. Information in this document has been carefully checked for accuracy at the time of printing; however, Cambridge Audio's policy is one of continuous improvement, therefore design and specifications are subject to change without prior notice. If you notice any errors please feel free to email us at: support@cambridgeaudio.com

This document contains proprietary information protected by copyright. All rights are reserved. No part of this manual may be reproduced by any mechanical, electronic or other means, in any form, without prior written permission of the manufacturer. All trademarks and registered trademarks are the property of their respective owners.

Class XD Technology International Patent Pending Cambridge Audio Ltd.

© Copyright Cambridge Audio Ltd 2007

Introduction

Thank you for purchasing this Azur 840W Class XD™ power amplifier. We hope that you will enjoy many years of listening pleasure from it.

The 840W features our unique proprietary amplifier topology; Class XD, designed to eliminate crossover distortion at low signal levels.

By actively displacing the crossover point this technology creates a region of pure Class-A operation where the crossover zone would otherwise be before moving into an enhanced form of Class B at higher levels. It should not be confused with Class AB, which gives a small area of Class A, but at the cost of higher distortion as soon as the signal level moves outside the AB area. Class XD circuitry not only removes crossover distortion from the zero-crossing point but also reduces distortion in other parts of the amplifier's output range.

A white paper on this patent pending technology is available on our website: www.cambridge-audio.com

Please note that because of the Class XD technology the 840W runs slightly warmer than a conventional Class B/AB amplifier and the ventilation slots on the top of the unit must not be obstructed.

Other features include a low resonance acoustically damped chassis for freedom from distortion inducing vibrations. Four pairs of very high current output transistors per output are used for excellent load driving ability, plus the unique fifth output transistor pair per channel that provides the business end of the Class XD circuitry. High quality polypropylene signal capacitors are used throughout, whilst multiple gold plated copper bus-bars provide very low impedance conduits for the power circuits and all resistors are 1% tolerance metal-film types.

Balanced audio input connections are fitted for the highest fidelity and all inputs have loop outputs. The loop outputs can be used with the 840W’s Bi-Amp Mono and Bridged-Mono modes to allow two or more 840Ws to be used in very high quality systems.

The 840W features separate transformer secondaries for left and right channels, twin rectifiers and separate PSUs for dual mono operation of the left and right power amplifiers.

Your power amplifier can only be as good as the system it is connected to. Please do not compromise on your pre-amplifier, source equipment, speakers or cabling. Naturally we recommend models from the Cambridge Audio Azur range, particularly the matching 840E pre- amplifier. These have been designed to the same exacting standards as this amplifier. Your dealer can also supply excellent quality Cambridge Audio interconnects to ensure your system realises its full potential.

Thank you for taking the time to read this manual; we do recommend you keep it for future reference.

Matthew Bramble,

Cambridge Audio Technical Director and the 840E/840W design team

4