Bookshelf Speakers — Mbl 120 MKII

The 120 MKII is the compact stand-mounted Radialstrahler from MBL International of Berlin and the smallest and least expensive entry of a loudspeaker lineup that also contains the 126 MKII, 116 F, 111 F, 101 E MKII and the 101 X-Treme MKIII system. This three-way model pairs omnidirectional radial drivers covering midrange and treble with two conventional woofers. The MKII update brings revised crossover networks with Intertechnik components, new WBT speaker terminals and two added colour schemes. MBL lists the pair at EUR 23,900, or EUR 25,720 when the stands are ordered too.

Key specs that matter

The crossover splits the signal at 650 Hz and 3,500 Hz. Bass comes from two 165 mm aluminium long-stroke woofers, and MBL gives the lowest frequency as 61 Hz and the nominal impedance as 4 ohm. Mounted on its stand it reaches 1213 mm in height, with the acoustic centre at 107 cm, and the footprint is 300 mm wide by 386 mm deep. A single speaker weighs 17.5 kg, or 28.0 kg together with the stand. MBL rates it for rooms up to 35 m2. Standard finishes combine a piano black or piano white body with gold or chrome accents, and custom colours are available to order.

Engineering and use context

Above the cabinet sit two Radialstrahler drivers, the MT50 midrange with a woven carbon fibre membrane and the HT37 tweeter in unidirectional carbon fibre. These drivers radiate through a full 360 degrees, and MBL uses this principle for every tweeter and midrange driver in its speaker line. The woofers are mounted on opposite side walls of a pyramid-shaped 20-litre enclosure in a push-push layout, and an aluminium strut joins the two drivers. The bass-reflex system is tuned to 42 Hz, and a 2-pole subsonic filter in the crossover protects the woofers below that range. For the first 120, designer Jürgen Reis gave a sensitivity of 79 dB at 2.83 V and 1 m on the axis level with the top of the tweeter magnet, which MBL names as the listening axis, and recommended amplifiers of 200 W into 4 ohm.

Pairing

With efficiency this low and a low nominal impedance, the 120 MKII needs a transistor amplifier with strong current reserves, and MBL's own Noble and Cadenza electronics, from the C51 integrated to the N21 MKII stereo power amplifier, are the in-house partners. Small valve amplifiers of a few tens of watts are not enough to drive it.

Alternatives

MBL makes no other bookshelf loudspeaker besides the 120 MKII.