The 851E excels in keeping the signal pure. Every component has been designed not to interfere with the audio signal input and output, meaning that the harmonic distortion and noise levels are so low they’re almost impossible to measure and certainly can’t be heard. A solid state volume control and toroidal transformer also contribute to the incredible sonic purity of the 851E. The toroidal transformer delivers a high quality power output to the amplification circuits with no clipping of the waveform signal, to provide a consistent signal with no transformer noise, buzz or hum. These expensive components coupled to countless hours of tuning mean the 851E delivers an incredibly pure signal to your amplifier.
To make the 851E compatible with as many sources as possible we built it with eight inputs, with three switchable between unbalanced RCA and high-end balanced XLR. There’s also a dedicated sub-woofer output for perfect integration with sub-woofers. Outputs include balanced XLR and unbalanced RCA connections for compatibility with any amplifiers and the 851E is designed as the perfect partner to the 851W; it has control bus connections for power syncing (switch one on and the other turns on also), and the Terrapin impedance buffering module enables seamless switching between sources. The result is a combination that’s comfortably the most musically thrilling we’ve ever made: detailed, powerful and pure.
When designing a stereo system, listeners are often encouraged to think about system matching, where components are handpicked to provide the best overall sound quality. People often assume this is due to the different audio characteristics, but frequently it is due to impedance (the relationship between voltage and current input/output) matching components. Products perform at their optimum when their input and output impedances match. This isn’t always possible though so we decided to develop our unique Terrapin impedance buffering module. This enables the 851E to be paired with a huge variety of audio sources and power amplifiers of varying impedance without risking any sacrifice in musicality or overall audio performance.
"With its 851E preamplifier and 851W, Cambridge Audio has built a pre/power combination that offers not only 'holy grail' audio performance, but also an almost complete suite of features and facilities. If you're in the market for separates (and you should be if you want seriously good audio!), this 851 duo should be high on your short list... if not at the very top of it. Highly recommended."
"Simply, this is one of the most transparent, thrilling and richly rewarding amplifier combinations I have encountered, with fine grip on the speakers with which it’s used, vast amounts of information delivered and never even the slightest sense of the music being held back or sold short."
"These amps represent a genuine introduction to true high-end amplification at the same time offering real value for money. Features-wise they’re fully loaded."
"I normally struggle to summarize reviews – however, in the case of the 851E/W, it’s simple. Buy it, and thank me later. Chances are you’re already raising a phone to your ear and calling your local dealer for a demo – if that’s the case, this review has served its purpose. If not, I suggest you do so now… if anything, you owe it to your music collection."
< 0.00045% @ 1kHz < 0.00057% @ 20kHz
< 110dBr < 90dBu
10Hz - 100kHz ± 0.1dB
8V RMS unbalanced 8V + 8V rms balanced
100 Ohms (Unbalanced or Balanced)
Flat or 200Hz 2nd Order Butterworth LPF
± 10 dB at 10 Hz
± 7.5 dB at 20 kHz
Black and silver
115 x 430 x 385mm (4.5 x 16.9 x 15.2’’)
851 Preamplifier, user manual, Remote Control, AAA battery x 3, Orange Control bus cable, power cord
The pre-amp stage is all about minimal colouration. Take the source signal and pass it onto the power amp stage with as little interference as possible. That’s exactly what the 851E does, and coupled with its solid-state volume control, it retains audio signal purity and precision even at the lowest listening levels.