Subwoofers — Lyngdorf BW-20

The BW-20 is a passive boundary woofer from the Danish company Lyngdorf Audio, designed to stand on the floor or be built into a wall and driven by an external amplifier. It carries two 12-inch woofers in a closed MDF cabinet and connects through Neutrik speakON terminals rather than line-level inputs.

Key specs that matter

Both drivers use aluminium cones, 67 mm voice coils, double spiders and large vented magnets, and their long-throw design allows an excursion of plus or minus 20 mm. Rated response runs from 19 Hz to 500 Hz at minus 3 dB, with the exact low extension depending on the equalisation applied. Nominal impedance is 4 ohm, IEC long-term power handling is 700 W, and maximum output reaches 118 dB SPL. The enclosure holds 64 litres and measures 450 mm wide, 710 mm high and 270 mm deep, and the unit weighs 35 kg. Only matte black is offered, and the warranty runs for 24 months. The Canadian list price is CAD 4,380.

Engineering and use context

Because the BW-20 has no amplifier, volume control, display or remote, all filtering and level setting happen upstream, and a crossover point between 60 Hz and 200 Hz is suggested. This high upper limit is unusually high for a bass unit and is the point of the boundary woofer idea, where this woofer covers the whole lower band and the main speakers only handle the range above. Placing the cabinet against a wall or in a wall cavity uses the boundary to reinforce output instead of fighting reflections from it. The shallow depth keeps the unit close to that boundary, and the closed box avoids port noise and port openings that would need clearance. The twin long-throw drivers with high excursion are there so the lowest frequencies can be reproduced at high level without reaching mechanical limits, which the high maximum output reflects.

Pairing

The BW-20 needs a dedicated power amplifier channel comfortable with a low nominal load, fed from a processor or amplifier that provides its own bass management and low-pass filter. Lyngdorf amplifiers with a woofer output suit this role, since the brand designs its boundary woofer concept around its own electronics, and in a 20 m2 room a single unit near the front wall is a typical starting point, with a second one possible for more even coverage.

Alternatives

The Lyngdorf BW-2 is a smaller active subwoofer of the brand with a single 10-inch driver and its own 400 W amplifier.