The 840C marks the zenith of Cambridge Audio's critically acclaimed Azur line up. Like all Azur products, the 840C promises unseen levels of performance and engineering excellence to the price points in question. But rather than redefining expectations in the entry-level market, the arena most often associated with Cambridge Audio, the company will reinvigorate the mid-end price sector. The 840C embraces a raft of proprietary technologies including ATFTM (Adaptive Time Filtering) asynchronous up-sampling technology which has been developed in conjunction with Anagram Technologies of Switzerland. This system intelligently interpolates 16-bit/44.1kHz CD data to 24-bit/384kHz data, through the use of a 32-bit Analog Devices Black Fin DSP (digital signal processor). This in turn feeds two 24-bit/384kHz DACs from the same company in dual differential formation. Each DAC handles just one channel for excellent stereo imaging, operating fully in differential mode for exceptionally low distortion and noise. Both unbalanced RCA and balanced XLR outputs are fitted. Two digital inputs are also provided which even allow the up-sampling and playback of other sources such as a DVD player via the Azur 840C. In addition, a recording digital output can even allow bit-for-bit data or upsampled data at 48, 96 or 192 kHz to be recorded by a suitable device. A Control Bus In/Out, an IR emitter in connection and an RS232 port are provided for easy multi-room connectivity. The RS232 protocol enables a two-way interface with third party home automation touchscreens. As with all Azur products, the foundation of the 840C's excellence is a bespoke chassis. This comprises an incredibly thick 7mm front panel and extruded side panels, both fashioned from aluminium, which combines with a 2mm formed steel base plate and specially designed vibration absorbing feet. The result is an ultra rigid, low resonance, acoustically dampened platform for the electronics to sit in.