AudioPro Blue Diamond review

Sit back and enjoy...

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I'm one of the Horribly Unashamed when it comes to low frequency reproduction. I like it loud, deeper than hell, very powerful, and able to scare the cat. I figure that if Jerry Bruckheimer or Steven Spielberg want me to jump clear out of my seat, then the reproduction system I'm using to enjoy their films should be able to do this for me.

Of course, that sort of massive scale and might will cost plenty, unless you choose very carefully from the equipment that's thought to offer synergy. Audio Pro consider themselves kings of synergy. Take a look at the imposing floorstanders included in this system. For the price of an upper-mid band set of five speakers, you are getting paired active subwoofers, as built in as well. This already looks like good value.

This review system actually comprises a pair of weird-looking surround lumps called QUBE, a centre speaker known as the Black Vector in its v.2 guise, and the aforementioned set of front left and right towers with active subwoofers in each, the so-called Blue Diamond (v.2) that lend this system its name.

Is it a mirage?

The QUBE is a product that is sold individually and reminds me powerfully of the intent behind the Mirage Omnipolar concept. Although not as wide-dispersing, their sloping faces still radiate sound. They have an angled top with an asymmetrical cloth and plastic grille to cover what is a cube with a diagonal slice lopped off the top.

They are arranged so the 5.25in driver and tweeter are pointing out at the listener from the rear corners, although they can obviously be used in subtle zone applications. They are ported underneath, where the hole can be stopped up with a supplied piece of foam pluggery if you wish. I preferred them unimpeded. They have four blunt conical feet underneath to hold the port the right distance above the surface they stand upon for some acoustic resistance. There are carefully shaped rubber feet supplied with adhesive layers of tape for sticking to these cones if you want to spread the load.

The centre speaker and the Blue Diamond towers all have super tweeters that reach a quoted 25,000Hz, yet the tweeters on the QUBE are 'better' in that they claim to reach 28,000Hz. The tweeters on the front soundstage speakers all live in floating die-cast aluminium sub-enclosures so as to keep their output clean.

The centre sports a 3.5inch midband driver beneath the tweeter to keep the horizontal energy dispersion more even, we are told. The left and right have a rear-firing port to help the 6in driver go with their tweeter, in a separate enclosure at the top of the tower.

The Black Vector centre speaker uniquely sports a passive radiator. This means that instead of a port, only one of the bigger 6.5in drivers is driven. The other allows the enclosure to breathe a bit and thus raises the efficiency to 89dB so it can keep up with the left and right towers a little better.

The Blue Diamonds each have fins on the back to allow cooling of their onboard 175W amplifiers. They also have an on/off switch, a sub-operating on/auto switch and knobs for both LFE input gain and master volume. The set is supplied with two long single core phono leads and a 'Y' lead.

You take the LFE feed from your amp and split it between the two boxes' inputs and then balance it all up. A little like balancing a broomstick on your nose, I had two master volumes, two phono level input controls and of course the LFE feed attenuator system from the reference Acurus ACT3 pre-power combo I use for this sort of thing to get hunky dory.

This was in fact a total doddle, although you do have to get up, sit down, go 'Hmm?' and do it again a couple of times before it sounds right rather than overblown. Once you have put the knobs in place, put on the pairs of white cloth gloves you have been using, as supplied, to install the system back in their cartons. It is time to enjoy....

Mixed and matched

Sometimes, I like to go retro and evaluate speakers with an old movie. My choice here was Jurassic Park, a home cinema classic with an awesome soundtrack and familiar sequences. I wanted to explore the depths of those twin subs, so started at the point where the water starts to shake in both the glass and the huge T-Rex footprint.

Immediately, despite the differences between the tweeters front-to-back, I could tell they were all voice matched. You get a fabulous three-dimensional sound field, in this case of surrounding jungle noises, along with a vocal clarity and perfection of placement that is truly exceptional.

When the bass comes along, it is fittingly impressive. The bass is rich, fat and drops deeply, if not quite as low as a reference quality sub, like my resident Rel can do. Rated down to 22Hz, I also tried my standard 16Hz 'can you cope' test from the old Mars Telarc recording. It was clear that something was rumbling even if they didn't reach fully flat down into the snake's belly zone.

Once again this is an impressive 5.1 system from Audio Pro. It delivers a superb all round performance, with great imaging, dynamics, clarity and intelligibility, even when it is under heavy drive, with bass that makes you look for paired coffee-table sized woofers that simply ain't there. Stylish and surprisingly good value, they are well worth auditioning. was the former name of Its staff were at the forefront of the digital publishing revolution, and spearheaded the move to bring consumer technology journalism to its natural home – online. Many of the current TechRadar staff started life a staff writer, covering everything from the emerging smartphone market to the evolving market of personal computers. Think of it as the building blocks of the TechRadar you love today.