Напольная акустика — Børresen Acoustics Børresen 05 Cryo Edition

The Børresen 05 Cryo Edition is the second of three 05 versions made by the Danish company Børresen Acoustics, between the standard 05 and the Silver Supreme Edition. The enclosure and its seven drivers are shared with the base model, and what changes is a cryogenic cycle applied to every metal component before the speaker is assembled.

Key specs that matter

The cryogenic step adds EUR 10,000 to the pair, taking the price from EUR 100,000 for the regular 05 to EUR 110,000, while the Silver Supreme model costs EUR 166,670. The edition arrived with the rest of the Cryo range on 4 March 2021. Quoted range is 25 Hz to 50 kHz, efficiency 90 dB per watt and the advised amplifier rating is above 50 W. Impedance stays above 5 ohm. One speaker is 155 cm tall, 30.5 cm wide and 58 cm deep, with a weight of 75 kg. The frequency split follows the same serial layout as the base model, with vacuum-impregnated coils and foil capacitors made to military specification. Adjustable feet under the base accept Darkz decouplers, and the reflex cabinet vents through three openings fitted with metal diffusers.

Engineering and use context

Treatment lasts three days of 24 hours. During the first the metal is cooled gradually from room temperature, during the second it stays around -196 degrees C and during the third it warms back slowly, since abrupt changes would build thermal stress into the parts. Børresen states that alloying elements are driven out of the grain structure so that the metal becomes very similar to a monocrystal. In this edition that includes magnets, pole rings, voice coil wire and crossover hardware. The driver array stays as in the base 05 - one ribbon planar tweeter with a 0.01 gram diaphragm, two bass/midrange units of 11.5 cm cone diameter and four of 15.5 cm. Their cones sandwich a Nomex honeycomb between carbon skins, and the iron-free motors keep coil inductance under 0.04 mH. Copper pole rings remain in place, which is the key hardware distinction from the Silver Supreme version.

Pairing

The high efficiency lets moderate amplifier power do the job, and the Aavik M-300 mono amplifiers from the same Danish group are one documented partner. The large enclosure calls for a room bigger than 20 m2 and for firm flooring that can carry the weight.

Alternatives

The Børresen 03 Cryo Edition applies the same deep-freeze process to the smaller five-driver 03 enclosure for EUR 67,500 per pair.