Напольная акустика — Cessaro Horn Acoustics GAMMA II

GAMMA II is built in Germany by Cessaro Horn Acoustics as a 5-way horn tower, the widest bandwidth split in its modular line. The bass horn can be configured as backloaded or frontloaded and fitted with either alnico or field coil drivers, so each system is specified to order.

Key specs that matter

Efficiency is 107 dB at 1 W/1 m with 8 ohm nominal impedance, and quoted bandwidth reaches from 28 Hz up to 45,000 Hz. Maximum output is above 130 dB and power handling is 60 W. The main unit is 212 cm high, 58 cm wide and 84 cm deep, while the active bass horn stands 210 cm high and 150 cm wide. Weight depends on the chosen bass horn configuration.

Engineering and use context

The company, led by founder Ralph Krebs, fits its horns with a one inch solid aluminium throat that bolts to the compression driver with no adapter, and damps the double wall with a heavy polymer fill. Its horn profile was derived over 2.5 years with in-house simulation software and softened at the mouth edge, the crossover is shaped around psychoacoustic properties of hearing, capacitors are silver MICAS parts and every internal run is pure silver wire. The bass section uses four to eight 16 inch alnico units or four to eight 18 inch field coil units, driven by two special solid state power amplifiers with a 1200 W transformer each, and a special version with up to eight power amplifiers is available. Field coil units are offered across bass, midrange and treble positions in the range. The low-mid band is an 11 inch alnico driver in a 103 cm spherical composite horn. A 2 inch TAD TD-4001 compression driver with a beryllium diaphragm covers the midrange in a 58 cm horn, a 1 inch TAD TD-2001 or TD-2002 handles treble in a 26 cm horn, and a modified TAD ET-703 with a cobalt magnet and beryllium diaphragm runs the super-treble in a 9 cm horn. Cessaro recommends a room larger than 40 m2 and a listening distance beyond 4.5 m. Composite horn colours and wood veneers for the cabinets are available on request.

Pairing

Cessaro lists 1.5 W as the lower limit for amplifier power and recommends high quality, fast amplifiers. With the bass powered internally, the external amplifier drives only the four upper bands, which leaves room for small single-ended tube designs.

Alternatives

Cessaro BETA II is a smaller 4-way tower from this brand with four bass units per channel and 105 dB efficiency.