Напольная акустика — Backes & Müller BMLine 100

The BMLine 100 is a fully active floorstanding loudspeaker made to order by Backes & Müller, the company founded in Saarbrücken, Germany, in 1973. It has been listed since 2012 and carries a price of about EUR 500,000 per pair. Backes & Müller builds its drivers by hand at its own headquarters, and paint for the cabinet is chosen freely by the buyer, since every pair is produced only after an order is placed. In the current catalogue it sits above the BMLine 80, BMLine 60, BMLine 50, BMLine 35 and BMLine 12 floorstanders.

Key specs that matter

Eight drivers per side are split across three frequency bands. Six 250 mm woofers handle the low end, each under DMC control, while the midrange and the tweeter are both cylindrical wave radiators. Every section has its own amplifier - 500 W for each of the six woofers, 300 W for the midrange and 200 W for the tweeter, which adds up to 3,500 W per speaker. Rated frequency response runs from 22 Hz to 22,000 Hz within 3 dB. One cabinet measures 100 cm wide, 230 cm high and 125 cm deep and weighs about 250 kg.

Engineering and use context

DMC is the Backes & Müller name for inductive negative feedback taken from the diaphragm itself, so the amplifier receives information about the actual cone movement. The crossovers are digital FIR filters designed for phase-equalised transitions between the three bands, and the upper range is handled by a NExT slot radiator that produces a cylindrical wavefront instead of a point source. The baffle is made of Corian, a dense solid-surface material. Because all amplification and filtering sit inside the cabinet, the owner does not choose or match amplifiers, and each speaker needs only mains power and a signal cable. With a height of 2.3 m and a quarter of a tonne per cabinet, delivery and placement need planning in advance, and the floor has to carry the load of two such units.

Pairing

Inputs are balanced analog on XLR and digital on AES, so the speaker can be fed from a preamplifier with balanced outputs or directly from a digital source or DAC transport with an AES output. Each cabinet also has a balanced XLR output that passes the analog signal on. Outboard power amplifiers play no part in the system, since each driver group already has a dedicated amplifier channel inside the cabinet, and the total output is spread across eight channels rather than one large output stage.

Alternatives

The Backes & Müller BMLine 80 is the smaller active floorstander of the same line, with six 21 cm woofers and a height of 210 cm.