Напольная акустика — Odeon Audio SEMPER

Standing 1.35 m high, the Semper is a full-range three-way horn speaker and, by Odeon Audio's own account, the second largest model in its range, below only the Carnegie. It is the middle one of three newer three-way models from the German workshop, sitting above the Helix. Odeon describes its shape as sculptural, and photographs from the maker show it in palisander, walnut root, walnut and white. Development, cabinet work and assembly take place in Germany, and every pair runs in for at least 24 hours before leaving the factory.

Key specs that matter

Rated sensitivity is 96 dB with an 8 ohm nominal load, and the quoted bandwidth runs from 28 Hz up to 28,000 Hz. Crossover points lie at 340 Hz and 2,400 Hz. Every cabinet is 135 cm high, 55 cm wide and 60.5 cm deep, with a weight of 84 kg. Treble is handled by a 1 inch ring radiator compression driver whose 38 mm Mylar diaphragm is moved by a 2.3 Tesla neodymium magnet, mounted in a 21.5 cm horn of birch multiplex. A handmade 13 cm midrange from a German maker, with a die-cast aluminium chassis, a 1.3 Tesla neodymium magnet and a cellulose cone of just two grams, works behind a 50 cm spherical wave horn. The low end uses a 13 inch Audax paper-cone woofer powered by an oversized ferrite magnet and derived from the driver in the Carnegie.

Engineering and use context

Odeon claims higher efficiency than the predecessor models, and the new enclosure puts all three drivers exactly on one axis for better phase and time behaviour. The cabinet is built in two parts from plywood, whose cross-glued veneer layers keep it stiff, together with an MDF up to 1.8 times heavier than the usual grade. Its asymmetrical bass section is a multiplex and MDF sandwich intended to suppress standing waves. The reflex tunnel points down and ends at the base plate. Inside the crossover, film capacitors from WIMA are joined by many New Old Stock bridge capacitors, and the Mundorf flat wire coils use paper insulation impregnated with resin to damp mechanical vibration. Parts hold a tolerance of one percent and are hard wired point to point by hand. OFC cable from German production feeds the woofer, while a thin 7N single crystal copper conductor in Teflon serves the high frequencies. WBT Nextgen gold-plated copper posts are fixed to acrylic carriers holding the crossovers, since Odeon avoids metal plates for their eddy current effects.

Pairing

The maker lists the Semper as compatible with every amplifier type, from quality solid state and valve units to low-power 300B triodes.

Alternatives

The Odeon Carnegie is a 155 cm tall horn speaker with a 38 cm woofer, rated at 97 dB and weighing 115 kg.