Bookshelf Speakers — M&K S300T Tripole

The S300T is a Tripole surround loudspeaker in the 300 Series from M&K Sound, the company founded as Miller and Kreisel. It is designed as the surround channel partner to the S300, using the same front drivers and crossover technology so that sounds panned between front and rear channels meet a matching driver set. The model carries THX certification for surround speaker duty and is sold in pairs, with a left and a right unit.

Key specs that matter

On the front sits a 6.5 inch glassfibre bass and midrange cone with a 1 inch soft fabric dome tweeter. Two isolated side chambers each hold a further pair of glassfibre drivers. M&K quotes a range of 80 Hz to 22 kHz within 3 dB, a sensitivity of 89 dB at 2.83 V and 1 m, and a 4 ohm impedance. Recommended amplifier power runs from 25 W to 400 W. The rear section measures 346 mm high, 345 mm wide and 180 mm deep, and the front face 345 x 227 x 180 mm. Weight is 12 kg for each speaker. Buyers can order it in either a black or a white satin surface.

Engineering and use context

M&K invented and patented the Tripole configuration. It combines the localised output of a conventional direct surround speaker, delivered by the front drivers, with the diffuse output of a dipole, delivered by the two side chambers. The aim is a continuous 360 degree field around the listening area, so that effects moving behind the seats, such as fly-overs, can be placed precisely while ambient content surrounds the audience. The side chambers are acoustically independent of each other and of the front section. The cabinet has an integral bracket for surface wall mounting, so it hangs flat on the side or rear wall and needs no separate stand or ceiling hardware. With its limited low-frequency extension, the speaker expects the processor to send deep bass from the surround channels to a subwoofer, which also relieves the amplifier channels driving it. In a larger layout, a pair of S300T units covers the side positions of a 5.1 system or the side and rear positions of a 7.1 system, where each unit's front drivers face the seats. Because the front section alone gives the localised part of the output, it should be aimed at the listening position rather than along the wall.

Pairing

The S300 in the same series is the direct front partner for left, centre and right channels, since both share drivers and crossover design. A multichannel receiver or power amplifier that stays stable into a low impedance load will drive it, and an M&K subwoofer can take the low bass redirected from the surround channels by bass management.

Alternatives

The M&K Sound S300 is the bookshelf-size front model of the same 300 Series, built with the matching front drivers and crossover.