Напольная акустика — Børresen Acoustics Børresen Z3 Cryo Edition

The Z3 Cryo Edition from Børresen Acoustics is the cryogenically processed version of the four-driver Z3 tower, the mid-sized floorstander in the Danish company's Z-series. Its layout is 2½-way, combining a closed ribbon, one 4.5 inch midrange unit and two 8 inch bass units set low on the baffle to couple more evenly with the floor and room. The cryo process is offered as a factory upgrade over the plain Z3 and cannot be added afterwards, since it has to be done to the parts before the speaker is built.

Key specs that matter

Rated bandwidth spans 35 Hz to 50 kHz. Sensitivity reaches 89 dB for 1 W into a nominal 4 ohm load, and Børresen recommends amplification rated beyond 50 W. Each cabinet is 102.5 cm high, 22.5 cm wide and 40.0 cm deep and weighs 35.5 kg. Buyers can pick black satin and white satin paint. The closed ribbon starts working at about 2.5 kHz and is itself rated at 94 dB, with a very light 0.01 gram moving mass.

Engineering and use context

For this edition every metal component in the speaker, from voice coils to crossover parts, is cooled to around -196 degrees Celsius in a slow three-day cycle. Børresen claims a gain of 6 to 8 percent in conductivity and a reduction in inductance from the process. The closed ribbon is described as an entirely new development, with finite element methods used to linearise and optimise its magnetic flux so the diaphragm moves freely while efficiency stays high. The cone drivers pair a carbon and Nomex honeycomb sandwich membrane of 5.5 grams, with the core 4 mm thick, with a motor carrying an 8 mm voice coil and just 0.06 mH of inductance, a figure Børresen puts at about a tenth of a conventional motor. The maker notes that these driver parts began as spin-offs from its 0-series research, which is how the Z-series brings them into a lower price class. Filtering is a parallel network assembled from the same exclusive parts found in the 0-series. At the base, adjustable feet accept Ansuz Darkz resonance control elements separated by titanium balls.

Pairing

The higher sensitivity makes this tower less demanding than the Z2, but the low nominal load still points to a transistor amplifier with a stable current supply. The slim cabinet with low-mounted woofers suits listening rooms of roughly 20 m2.

Alternatives

The Børresen Z5 Cryo Edition carries the same treatment into a 151 cm tall cabinet with four woofers and a 25 Hz lower limit.