Напольная акустика — Fischer & Fischer SN/SL 370 AMT

The SN/SL 370 AMT is a passive floorstanding loudspeaker from Fischer & Fischer, the maker in Schmallenberg, Germany, that builds every cabinet from natural slate. In the brand's current range it is the only 2½-way design, placed between the two-way SN/SL 270 models and the three-way SN/SL 470. The SN letters denote a natural slate surface, while SL marks a version that is polished, then coated in any RAL shade or an available car colour.

Key specs that matter

Two 180 mm Fischer & Fischer cone drivers share bass and midrange duty. Their membranes are a sandwich of carbonized paper and carbon foil, and each carries an aluminium phase plug. Upper frequencies are left to an Air Motion Transformer made to order for the brand by Mundorf. The maker lists a range of 36 Hz to 27,000 Hz within 3 dB, a 4 ohm impedance, sensitivity of 90 dB at 1 W and 1 m, and 112 dB as the highest acoustic pressure. The slate cabinet alone measures 1096 x 220 x 300 mm (H x W x D), growing to 1141 x 305 x 350 mm on its aluminium floor system, and one speaker weighs 69 kg.

Engineering and use context

Bass loading uses a reflex port. Its crossover is described as a phase and impedance corrected filter of 1st and 2nd order. The cabinet walls are 20 and 23 mm thick slate. Fischer & Fischer states that the flaky, layered structure of the rock and its very high mass keep panels from resonating, so wooden cabinet vibration is avoided, and that the finished enclosures are sized for living spaces. The brand also says its speakers can be updated to newer technology years after purchase. The aluminium feet can be levelled on uneven floors. The company notes that the slate it uses was compressed from ancient soil over almost half a billion years, and that in the treble region the mass of the baffle prevents it from resonating along with the moving membrane. Fischer & Fischer also says it sources drivers and parts from leading manufacturers worldwide.

Pairing

The rear panel is bi-wired, with rhodium plated 63 A terminals joined by pure silver bridges, letting the speaker run from a single amplifier channel per side with one cable, or take separate cables to its high and low halves. Choose an amplifier whose load rating covers this slate model at its nominal figure.

Alternatives

Within the same slate range, the Fischer & Fischer SN/SL 470 is a three-way model with a dedicated midrange driver and a quoted weight of 89 kg.