A couple of years ago German loudspeaker maker ELAC employed ex KEF and TAD engineer Andrew Jones, it proved a good move especially when the budget Debut B6 garnered itself so many awards. Since then Andrew has introduced his favourite loudspeaker technology to ELAC’s range in the form of concentric mid/treble drivers, where the high frequency dome sits in the middle of a midrange cone. These are available on a number of models including the top of the range Adante AF-61 floorstander and the Uni-Fi Slim models of which the B5 U5 is the most affordable. It gets the slim moniker because there is a version with the same drivers in a wider box called UB5, but that model was considered a little too husky for European markets.
The B5 U5 Slim has a 5.25inch bass driver and a concentric 4 inch midrange with a one inch tweeter at its centre, both cones are aluminium and the tweeter has a soft fabric dome. The accepted benefit of concentric or coaxial drive units is that that a wider range of frequencies come from a single point source which should benefit coherence and imagine, one disadvantage is that the tweeter is effectively horn loaded by the midrange. Nonetheless it’s a technology that has been used by some very successful brands including Jones’ former employers and Tannoy among others. The sensitivity rating here is a lower than average 85dB with a nominal impedance of four Ohms, figures that combine to suggest a reasonably powerful amplifier is necessary to get the best out this slick box.
A rear reflex port means that you will need to leave a bit of space behind them to avoid excess bass, while a single pair of rather nice cable terminals means you don’t need to even think about bi-wiring, I try not to but there are those that do. The cabinet is a svelte 178mm (7inches) wide and comes in matte black or white paint finishes. There are grilles in the box that attach magnetically which avoids unsightly fixings on the front of the speaker.
Sound quality
I placed these ELACs on 60cm Stand Design stands and used a forthcoming Cambridge Audio power amplifier with considerable power reserves. This brought forth plenty of detail without any forwardness thanks to a slightly smoothed top end, the image produced lacked a little openness but wasn’t particularly shut-in either. Bass weight is good for the size with plenty of power if slightly limited dynamics, but in the all important timing stakes the ELAC is largely transparent to the source and amplifier. I enjoyed Ryan Adams’ last album Prisoner which was nicely detailed and precise albeit with the slightly hardened edge of the production held back a little. While male voice on JS Bach’s St Matthew’s Passion was deep and rich if slightly lacking in the requisite height. Amandine Beyer’s violin gave up lots of texture while the Grateful Dead’s ‘Wharf Rat’ proved to be a delightfully rambling tune that couldn’t be put down in the ELAC’s hands.
Moving over to my regular power amp, the ATC P1 and Blues for Allah on the turntable helped open up the sound even if the volume had to be wound up quite a bit to get sufficient level. The guitar line was a little smoother than usual but the bass line tripped along a treat and the speakers managed to put up a decent image in the process. With more familiar material the sound continued to escape the boxes well but didn’t encourage high level listening, this may not be the ultimate headbanger’s speaker but that’s hardly its MO. With wooden stands from HiFi Racks I got better bass definition and weight which produced a more solid image, but timing suffered a little on the more challenging material. But the spatial dynamics and rich tonal character of acoustic instruments made up for this to a large extent. The final amplifier I tried was Rega’s Brio integrated, the least powerful of the three this produced slightly restrained dynamics with soul singer Dwight Trible but excellent image subtlety. Another piece sounded appealingly tight and springy in classic Rega style, with good extension in the bass and no sense of there being a port on the box, which is an achievement in itself.
Conclusion
Clearly amplifier choice is important with this speaker, especially with regard to how great a sense of space they can achieve. The top end is a little polite which is quite helpful with some material but the bass is taut and sufficiently extended for the price, what’s more it can deliver the timing nuances of the Grateful Dead, which a good sign. Of the three amps tried I found the little Rega the most enjoyable if least detailed, the ELACs sound wonderfully nimble and upbeat in its hands and the smoothness of the top end compensates for the slightly unrefined elements of the amp. The Uni-Fi B5 U5 Slim does a decent job given the constraints of its size and nature, you get a lot of drivers for such a compact cabinet and while that undermines sensitivity it clearly doesn’t compromise entertainment potential.