Loudspeakers

When Q Acoustics launched its Concept loudspeaker range in 2013, it began with a sub-£500 standmount – the Concept 20 [HFN Feb '14]. While this was in keeping with the value-for-money reputation the UK brand had developed since its arrival in 2006, within a few years it was reaching higher with the (then) £3000 Concept 300 and £4200 flagship Concept 500 [HFN Jul '17].

With the new £1999 Concept 50 reviewed here, plus companion £899 Concept 30 standmount, Q Acoustics has finally filled the obvious gap in its range. Yet it's keen to point out the new models should be viewed more as trickle-downs from the Concept 300/500, and not merely an update on (or replacement for) the older Concept 20/40.

A two-way floorstander with an MTM driver configuration, the '50 is available in black, white or silver gloss finishes, minus the wood veneer details of the Concept 500. It's certainly no less visually appealing, just more modern, with curved edges to the cabinet performing the magic trick of making it appear more slender than its modest 180mm width might suggest.

Cabinet Blueprint
The Concept range is all but defined by its innovative triple-layer cabinet design and the '50 is no exception, combining the Gelcore damping, FEA-modelled internal bracing and Helmholtz Pressure Equaliser (HPE) tubing seen in the '500. Yet this is where the trickle-down technology – for the most part – ends, as the Concept 50's bass/mid and tweeter are new 'ground-up' designs, albeit utilising similar materials (coated paper for the bass/mid, fabric dome for the tweeter) as for the rest of the Concept range.

The drivers' diecast chassis are fixed to a rigid, 3mm-thick aluminium baffle, shaped to provide 'smooth, low acoustic diffraction', which then attaches to the cabinet by spring-tensioned bolts that extend through to a corresponding plate on the rear baffle. Furthermore, the dome tweeter, which sits within a shallow waveguide and features an inverted roll surround to improve its dispersion, is 'dynamically' isolated from the baffle. The 125mm bass/mid, meanwhile, features a 30.5mm voice coil, plus Nomex spider and FEA-optimised rubber surround.

Crossover Optimisation
The crossover point is given as 2.1kHz, made possible, says Q Acoustics, by its tweeter's low 700Hz resonant frequency and low measured distortion above 1.5kHz. As is not uncommon these days, this network is mounted onto the Concept 50's cabinet base, ensuring the components are withdrawn as far as possible from the drivers' magnetic fields and unwanted vibration.

This base plate itself has also been designed with an eye on acoustic benefits. Formed of three layers (upper and lower aluminium, between which resides a layer of moulded 'isolation spheres'), it acts to decouple the cabinet as far as possible from the supporting surface, in my case the floor. To this you attach the Concept 50's feet, small at the front but as wide curved outriggers at the rear,

all with adjustment so you can engineer a little 'tilt' to keep you on-axis with the tweeter. Note that the base plate allows for a 'calculated degree of movement', but can be locked via Allen fixings if a third-party isolation base is to be used.

While those long feet take the assembled speaker's full width to 418mm, this isn't an awkward floorstander to install. Foam bungs are provided for its rear-facing bass port, although the minimum recommended rear wall distance is a meagre 20cm (with 50cm from side walls a suggestion). Q Acoustics rates the Concept 50 at a very generous 90.5dB sensitivity with a minimum 3.6ohm impedance, figures that are in close accord with PM's independent Lab Report.

Concept Blasts Off
I won't beat around the bush: these loudspeakers are an absolute blast. Not from the perspective of absolute detail or transparency, as there's evidence of the Q Acoustics 'house sound' in the way the Concept 50 massages treble, and plumps up bass and lower mid. Yet this voicing isn't done clumsily, resulting in an engaging but not too eager-to-please overall sonic signature. There are robust lows and sweet highs, accompanied by a scale of soundstage that you might not expect from cabinets of such modest dimensions. Most importantly, listening to the Concept 50 never had me wondering about the price tag – I was too busy enjoying myself.