Напольная акустика — Wolf von Langa SON WVL 12639 SON

The WVL 12639 SON is a compact two-way floorstanding loudspeaker from Wolf von Langa, a workshop in Neunkirchen am Brand in Bavaria that specialises in handmade speakers with field-coil drivers of its own making. Instead of a permanent magnet, the bass-midrange unit gets its magnetic field from a coil fed by an outboard current supply, and the maker describes the SON as a compact design within its range. Pricing is USD 17,995 per pair in the United States and EUR 14,990 in the Netherlands.

Key specs that matter

Wolf von Langa lists a response of 20 Hz to 25,000 Hz, an efficiency of 94 dB at 1 W and 1 m and a nominal load of 8 ohm. Continuous power handling is 150 W, with a peak capability of 1,500 W for 10 ms. Each cabinet measures 404 mm wide, 872 mm tall and 300 mm deep and weighs 42 kg with its acoustic grilles fitted. The standard finishes are ultra gloss black and white, and a bamboo veneer has also been offered.

Engineering and use context

The low and middle frequencies come from the in-house AC-2676 field-coil driver with an effective cone diameter of 258 mm. Its hydrophobic paper cone is made from polysaccharides and silk fibres, and the underhung voice coil is wound edgewise from flat copper-coated aluminium wire. On the back of the cabinet a 12-inch aluminium passive radiator on a rubber surround works on the Helmholtz resonator principle. Treble is handled by a dipole Air Motion Transformer that Mundorf builds to Wolf von Langa specification, sitting on top of the cabinet and held by magnets so its position can be shifted for time alignment. The enclosure is high-density fibreboard with a PMMA coating on both sides and an aluminium front baffle about 10 mm thick, and three M8 threaded holes front and back accept the owner's choice of feet. A split crossover with pure copper air-core inductors and low-loss film capacitors divides the band at 800 Hz. Each speaker connects by two 3 m leads to a current-source supply, so no mains cable runs to the cabinet itself. Field current is variable from 0.0 to 3.0 A, and the pair is calibrated at the factory with a suggested starting value. The supply uses a Hirschmann ST-series industrial connector, and a 5-year warranty applies after registration.

Pairing

High efficiency and a benign load let modest amplifiers, including valve designs, drive the SON well within its power handling. WBT nextgen terminals on separate high and low sections accept bi-wiring or a pair of stereo amplifiers for bi-amping.

Alternatives

The Wolf von Langa WVL 23239 CHICAGO is a larger three-way open U-baffle design with two 15-inch field-coil bass drivers.