Cambridge Audio Azur 851A Class XD Integrated Amplifier

Cambridge Audio Azur 851A Class XD Integrated Amplifier Introduction

I bought this amplifier new in 2015. Used sparingly and in very good condition. Reason for selling is I bought a Bryson. There is not much difference in music clarity or definition other than the Bryson is 300 watts per channel into 8 ohms while the Azur 851A is 120 watts into 8 ohms. Not willing to negotiate on price. The 851A 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 the other parts of the amplifier’s output range. This 851A features our latest development of Class XD with many tweaks and enhancements from our on-going research resulting in our best sounding implementation to date. 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 851A runs slightly warmer than a conventional Class B/AB amplifier and the ventilation slots on the top of the unit must not be obstructed. A new balanced volume topology has been implemented for this model, controllable in 1 dB steps over most of the range, giving very fine control, an accurate logarithmic law and superbly accurate channel balance. Input switching is by high quality gold contact relays. The 851A features separate transformer secondaries for left and right channels, twin rectifiers and separate PSU’s for dual mono operation of the left and right power amplifiers. A separate transformer supplies the preamp making the 851A effectively a Pre and Power amp combination in one box. Balanced as well as unbalanced inputs are featured for Sources 1 and 2 giving optimal performance with equipment such as the matching 851C Upsampling CD player which features balanced outputs. The casework combines massive structural rigidity with careful damping and control of acoustic resonance. An Azur Navigator remote control is also provided, giving full remote control of your amplifier in an attractive and easy to use handset. Control Bus Input/Output, IR Emitter Input and RS232 control are featured making it easy to integrate the 851A into a Custom Installation system if desired. Your amplifier can only be as good as the system it is connected to. Please do not compromise on your source equipment, speakers or cabling. Naturally we particularly recommend models from the Cambridge Audio Azur range. 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 realizes its full potential.