Полочная акустика — DALI OPTICON LCR MK2

DALI describes the OPTICON LCR MK2 as a multipurpose on-wall speaker from its OPTICON MK2 range, suitable for the left, centre or right position in a home cinema or as a pair for stereo listening. The Danish company introduced the MK2 version in February 2021 at a US price of USD 1,099 per speaker. Despite a cabinet depth of just 127 mm, it carries a full-size woofer and the brand's hybrid tweeter module.

Key specs that matter

The OPTICON LCR MK2 is specified from 70 Hz to 30,000 Hz within 3 dB. Sensitivity reaches 89 dB for 2.83 V at 1 m, and the nominal impedance is 4 ohms. Maximum output is given as 109 dB SPL at 1 m. DALI calls the layout a 2 + 1/2-way design, with crossover points at 2,800 Hz and 14,000 Hz. The high frequency section pairs a 29 mm soft dome with a 17 x 45 mm planar element, and a single 6.5 inch unit covers the low and middle frequencies. The maker recommends amplifiers of 30 to 150 watts. The cabinet stands 482 mm tall and 285 mm wide, and finishes listed for the model are satin black, satin white and tobacco oak.

Engineering and use context

The half-way element is the planar tweeter, which joins the dome above the upper crossover point and takes over the highest frequencies. In the woofer, a cone of paper pulp mixed with wood fibre is used to keep break-up resonances low. The magnet system relies on SMC, a soft magnetic compound that DALI uses to cut mechanical distortion that arises from eddy currents and hysteresis, and the company reports a large drop in third-order distortion as a result. The front baffle is 25 mm thick and extra internal bracing stiffens the enclosure. A bass reflex port tuned to 45.5 Hz is placed on the rear of the cabinet, so the gap between speaker and wall becomes part of the bass loading. DALI states that the port reduces woofer distortion and controls the time response of the bass roll-off, and it tuned the design to perform best 0 to 10 cm from the wall. A keyhole bracket takes care of mounting, the grille is removable, and four rubber bumpers are supplied. One pair of binding posts accepts the cable, with no bi-wiring or bi-amping.

Pairing

With this low impedance, the amplifier or AV receiver should be rated to drive such loads, while the good sensitivity keeps the power needed for normal levels moderate. Three units across the front wall form a matched left, centre and right array for a surround system.

Alternatives

The RUBIKORE ON-WALL is another DALI wall speaker, likewise fitted with a hybrid tweeter, rated at 88.5 dB sensitivity.