Полочная акустика — KEF Q350

The Q350 is the larger of the bookshelf pair in the 2017 KEF Q Series, the eighth iteration of this line, which also included the smaller Q150, the Q550, Q750 and Q950 floorstanders and the Q650c centre model. The launch price in Britain was GBP 530 per pair and the US price USD 650 per pair. The pair comes in two colour options, Satin Black and Satin White, and ships with rubber feet.

Key specs that matter

KEF built the Q350 as a passive two-way bass reflex cabinet with a single Uni-Q array, combining a 165 mm aluminium low frequency cone with a 25 mm vented aluminium dome placed at its centre. Crossover is at 2.5 kHz with first order slopes. Rated response is 63 Hz to 28 kHz at plus or minus 3 dB, and the free field extension is 42 Hz at -6 dB. Sensitivity reads 87 dB for 2.83 V at 1 m, and maximum output is 110 dB. Impedance is 8 ohms nominal and 3.7 ohms at minimum, while KEF asks for 15 to 120 W of amplifier power. Its enclosure is 358 mm high, 210 mm wide and 306 mm deep, rising to 362 mm on its rubber feet, and one speaker weighs 7.6 kg.

Engineering and use context

KEF revised the Uni-Q for this series with a Damped Tweeter Loading Tube, intended to improve the lower treble region, and the crossover gained a low distortion inductor for the bass section. In the older bookshelf models the reflex port sat on the front baffle - here it moved to the rear panel to reduce midrange leakage, and its profile comes from CFD computer modelling of air flow. The coaxial array now sits in the middle of the cabinet, which KEF says lowers internal resonances. Against the Q150 the larger cone and cabinet let the Q350 reach 5 Hz lower, with 1 dB more sensitivity and 2 dB more maximum output. The baffle carries no visible screws, the cabinets have a matt satin finish, and full length magnetic grilles are an optional accessory.

Pairing

The impedance dip and the recommended power range point to an ordinary transistor integrated amplifier or AV receiver rather than a very small valve unit. In a 20 m2 room the pair can serve as main stereo speakers or as front speakers beside the Q650c centre.

Alternatives

The KEF Q150 is the compact sibling from that 2017 line, with a 130 mm Uni-Q driver, 5.6 kg per cabinet and a price of GBP 430 per pair.