Impressively relaxed soundstage, failsafe protection systems, performs above its price
Prefers easier-driving speakers
The bumf for the new Azur amplifiers doesn't go into Cambridge Audio's 30-year history but this is a brand with form, of a sort. Not surprisingly it doesn't mention the ups and downs it had prior to the name being purchased by the Audio Partnership, Richer Sounds' in house design and manufacturing arm, in the nineties, since when it has run on a somewhat more even keel. When it was founded in the seventies it created some great amps and tuners and went on to produce some of the most ambitious if not most reliable CD players of the eighties, including one of the very first two-box designs.
Cambridge is now a successful budget brand with a design team in the UK and manufacturing facilities in the factory of the world, China. This is a manufacturing model you'll find with a number of budget brands because it's the only way you can make a decent component at a competitive price.
The Azur 640A is the bigger by 15 watts of two externally identical Cambridge amps, its twin being the 540A at £200. The 640A is specified at 65 watts into eight ohms with a wide claimed bandwidth of 5Hz to 50kHz. It has plenty of features because knobs clearly sell at this end of the market, fortunately the bass and treble controls (considered largely extraneous if high fidelity is the goal) can be bypassed courtesy of a direct button. The amp even offers the option of a moving magnet phono stage for those who appreciate vinyl.
Inside the matt silver casework there is a wealth of protection systems, both for the amp itself and the speakers it is hooked up to. These include a clipping sensor, temperature sensor and something called CAP5 which is a means of monitoring the amp's behaviour to make sure that nothing untoward happens in the event of a problem, be it with the amp itself, or the load it's driving - such as a shorted speaker. A form of feedback loop, it measures the distortion in the output signal relative to that at the input, and from this it can tell when the unit is being clipped or overdriven and apply protection if necessary. It even checks for short circuits and faults every time you switch on. It might make Cambridge seem unduly nervous but there's a lot to be said for a failsafe product, especially if as the company claims, it has no effect on the sound quality.
Put in charge of the fairly average load presented by a pair of Cyrus CLS50 speakers this smart little sound surfer delivers a good three-dimensional soundstage that is detailed without being in your face, in fact by the standards of most budget amplifiers it's impressively relaxed. It reveals subtle details quite effectively, bringing colour to treble rather than pure shine and delivering music with a perky sense of time.
With heavy jazz renderings it delivers plenty of instrumental energy in a steady and engaging manner. Only over an extended period does challenging music begin to assault the Azur's sense of equilibrium by starting to sound a little hard. Vibrant world music makes for much more comfortable listening, the amp revealing good transparency and dynamic enthusiasm when presented with suitably lively material.
This Cambridge has a more weighty sound than much of the competition at this price, the obvious alternatives being brands such as NAD and Rotel which don't have quite the finesse when it comes to building tension that the 640A displays. Ambient dance grooves reveal its impressive bass kick and ability to track energy build-up rather effectively, the sound pulling you in and engaging your attention.
As is my wont I tried playing some vinyl albeit through one of the aux inputs as my sample didn't come with a phono stage. With a Clearaudio Emotion turntable and Trichord Dino+ phono stage it was not difficult to hear the classic vinyl virtues shine through, a latin rock album sounding as energetic as ever thanks to its enthusiastic percussion section. I also gave the amp a spin on a more challenging pair of speakers, the excellent ATC SCM35s just to see how far its 65 watts could go. While the result was perfectly open and engaging it didn't encourage high-level or extended listening and you'd be better off sticking with speakers offering easier loads. Look for sensitivity of 89dB or higher and avoid anything with a four-ohm impedance.
The Cambridge Azur 640A is a shining example of what can be done at this challenging price point. It seems more than capable of holding its own against other amplifiers in this arena and could probably show amps costing £100 more a thing or two about the subtleties of musical entertainment.
Hi everybody. I'm currently using the Azur 640A and running a classic pair of Snell JII speakers, and the sound is amazing, running through my HP desktop and a Creative Soundblaster XTreme Music soundcard (great staging capabilities). Here's my question: I want to add two speakers to the mix without paying a fortune, just to enrich what is already rich! I'd like to know 1. If I can add 8 Ohm speakers (such as the Polk tsi200 model) to run parallel with the Snell JIIs, which are 4 Ohm speakers? And, 2. if so, will they drain the power and thus diminish the sound quality of the Snells as is right now?
Thanks if anybody has tried such a configuration. They sound awesome now, but it would be nice to add another set for fun.