Полочная акустика — Revel M126Be

The M126Be belongs to the PerformaBe series from Revel, a range built around a pure beryllium tweeter. Revel pairs a 25 mm beryllium dome with a 6.5 inch woofer and a high-order crossover, in a curved cabinet with a bass reflex port.

Key specs that matter

The woofer cone is a Deep Ceramic Composite aluminium diaphragm mounted in a cast frame. The tweeter sits in a 5th-generation Acoustic Lens waveguide, and the filter divides the band between the two drivers at 1.7 kHz. Revel quotes a frequency response of 46 Hz to 40 kHz at the -6 dB points, a sensitivity of 86 dB at 2.83 V and 1 m, and a nominal impedance of 8 ohm. Revel recommends amplifiers of 50 to 150 W. Each cabinet measures 386 mm high, 211 mm wide and 262 mm deep and weighs 10.0 kg. Buyers can choose high-gloss black, white, metallic silver or walnut.

Engineering and use context

Beryllium has roughly half the mass of aluminium, titanium and diamond, yet Revel states it is up to 4.5 times stiffer than those two metals, while its high thermal conductivity helps cool the voice coil. The waveguide geometry is calculated to match the dispersion of the tweeter to that of the cone driver around the crossover region, and it widens tweeter dispersion above that range. For the DCC cone, the aluminium is exposed to an intense plasma discharge that fuses a deep ceramic layer onto both sides, stiffening and damping the diaphragm to reduce cone resonance, while the cast frame removes another resonance source. The port is designed with fluid modelling and carries matching flares on its inner and outer ends to limit port noise and dynamic compression, and foam plugs for the port come in the box. The enclosure uses 25 mm thick panels formed from contiguous wood layers, with internal bracing. The midrange and tweeter circuits of the crossover use film capacitors and air core inductors. A finishing process developed by Italian luxury cabinet makers gives the gloss surface, and magnets hold the grilles, leaving the baffle free of visible fixings.

Pairing

The M126Be offers one pair of gold-plated terminals, so it is wired with one cable per speaker. Revel's cable table asks for thicker wire as runs get longer, for example at least 16 AWG for runs under 3 m and 12 AWG for runs under 7 m, because a loop resistance above 0.07 ohm per run mis-terminates the filter network.

Alternatives

Another Revel bookshelf design is the Ultima2 Gem2, a three-way model with a beryllium tweeter, a 4 inch midrange and an 8 inch woofer.