Cambridge Audio Azur 851A review

For scale and power, not to mention build and style, the Azur 851A is hard to beat Tested at £1200

What Hi-Fi? Verdict

For scale and power, not to mention build and style, the Azur 851A is hard to beat


  • +

    Solidly built, smartly turned out

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    Clear display

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    Array of inputs

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    Big, powerful sound


  • -

    Lacks organisation and poise when really pushed

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“The finest-sounding components Cambridge Audio has ever made.” That was the claim when the flagship Cambridge Audio 851 Series broke cover at the start of the year. It’s been a long time coming but we’ve finally got our hands on (and ears around) the Azur 851 amplifer, so we can see if the company’s hype is justified.

If not quite a departure, it’s certainly a foot in a new direction for the British hi-fi stalwart.

Previously preoccupied with the budget market, Cambridge Audio has made a habit of being as reliable as a Swiss timepiece when it comes to delivering great-value hi-fi separates for not a lot of cash. Cambridge Audio kit is as much of a rite-of-passage for any music lover as the prerequisite trip to Richer Sounds.

The 851A amplifier – and its partner, the 851C CD player – sell for £1200 a piece and are the products of two years of R&D at the company’s London HQ.

Cambridge Audio 851A: Tech specs

The Azur 851A develops Cambridge Audio’s proprietary Class XD power supply and delivers a hefty 120 watts of power per channel. Two toroidal transformers are used, one each for the preamp and power amp sections; the 851A is effectively a pre- and power-amp combination in one box.

Cambridge Audio 851A

Cambridge Audio 851A

Round the back you’ll find a healthy selection of inputs: two sets of balanced XLR inputs, seven RCA line inputs, tape loops and preamp outputs. There are control bus and IR connections too, while the twin speaker terminals make it easy to biwire your speakers. You can also plug in Cambridge Audio's iD100 iPod/iPad dock, although you'll need to add a DAC between it and the amp.

We have no issue with build quality or design here. The 851A looks workmanlike but immaculate in silver or black, and the full-metal chassis feels solidly built, with high-grade components from the speaker terminals to the control knobs.

The large front-panel display is clear and useful, and there’s the option of renaming any of the inputs. There’s a brand new remote control, too: it’s comfortable and satisfying to use, and can also control your iOS device through the iD100 dock.

Cambridge Audio 851A

Cambridge Audio 851A

Cambridge Audio 851A: Sound quality

We get down to business and take a listen to one of our favourite and, handily, most testing albums of recent years, Radiohead’s In Rainbows.

There are intricate drums, atmospheric vocals (with at times tricky-to-decipher lyrics) and plenty of dynamic highs and lows. And for that ‘just like being there’ listening experience, the Cambridge Audio delivers in spades.

Huge scale and power is relayed as required, that mighty power output showing its hand, and there’s plenty of deep, good-quality bass.

James Blake’s I Never Learnt To Share shows the 851A is no balls-out oaf, however, with impressive transparency across the sonic spectrum and a clean and clear treble.

The track builds to a noise crescendo, and while there’s no issue with dynamics, it’s not quite as controlled and organised as some rivals, and we strain to pick out finer details.

Switch to some hi-res classical music and again, when really pushed, you can spot this occasional lack of poise.

Cambridge Audio 851A

Cambridge Audio 851A

Cambridge Audio 851A: Verdict

But if it’s room-filling sound with impressive clarity, weight and bags of power, then the Cambridge Audio Azur 851A should be on your list.

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What Hi-Fi?

What Hi-Fi?, founded in 1976, is the world's leading independent guide to buying and owning hi-fi and home entertainment products. Our comprehensive tests help you buy the very best for your money, with our advice sections giving you step-by-step information on how to get even more from your music and movies. Everything is tested by our dedicated team of in-house reviewers in our custom-built test rooms in London, Reading and Bath. Our coveted five-star rating and Awards are recognised all over the world as the ultimate seal of approval, so you can buy with absolute confidence.

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