Напольная акустика — Cessaro Horn Acoustics ALPHA II

ALPHA II is the 3-way entry model among the Cessaro Horn Acoustics floorstanders made in Germany within its modular line. Owners can later convert it to the BETA II or GAMMA II by buying the additional parts, so the cabinet is not a dead end once a larger room or a bigger system is planned.

Key specs that matter

Efficiency is 98 dB at 1 W/1 m into a nominal 8 ohm load, and the stated frequency range runs from 34 Hz to 45,000 Hz. Power handling is 300 W and peak level is stated as over 122 dB. The cabinet stands 176 cm tall, 58 cm wide and 84 cm deep. In plywood construction a single speaker weighs 210 kg, while the composite version reaches 340 kg per unit.

Engineering and use context

Cessaro was founded by Ralph Krebs, and the company spent two and a half years with its own simulation software developing the spherical horn profile, which is modified at the mouth for a softer wave at the edge. Each horn uses a double shell filled with a dense polymer for damping, and the throat is a solid aluminium ring one inch thick that couples directly to the driver without an adapter. A 16 inch alnico bass driver sits in a backloaded horn made of plywood or composite. Midrange duty goes to a 2 inch TAD TD-4001 alnico compression unit whose diaphragm is beryllium, integrated into a composite spherical horn, and the crossover to the bass unit sits at around 500 Hz. Above it a modified TAD ET-703 with a cobalt magnet and a 0.5 inch beryllium diaphragm handles treble, mounted in a spherical horn milled from brass. The maker suggests a space above 20 m2 and a listening distance beyond 2.5 m. The mid horn of an Alpha model weighs about 60 kg on its own. Crossover parts include high value pure silver MICAS capacitors, the network is laid out around psychoacoustic priorities of human hearing, and internal wiring is pure silver throughout. Most drive units in the range are custom TAD types. Composite horns can be ordered in custom colours, and a choice of wood veneers is offered for the cabinet and side panels.

Pairing

Anything above 1.5 W meets the stated minimum, and Cessaro wants a quick, high grade amplifier to realise the full potential of the design, so low power tube and solid state units both fall within its stated range.

Alternatives

Cessaro BETA 0.5 II is a 4-way floorstanding horn system of the same brand with two external active backloaded bass horns and 100 dB efficiency.