Напольная акустика — Børresen Acoustics Børresen 02

The Børresen 02 is the base version of the smaller floorstanding model in the 0-series from Børresen Acoustics, a company belonging to Audio Group Denmark. It uses copper pole rings and untreated metal parts, which separates it from the Cryo and Silver Supreme editions of the same cabinet. The drivers, crossover and enclosure are designed and assembled in-house by the company.

Key specs that matter

Three drive units sit in each cabinet - one Børresen RP94 planar ribbon tweeter and a pair of 5 inch iron-free bass/midrange drivers. The maker lists a response of 40 Hz to 50 kHz, a sensitivity of 88 dB at 1 W, an impedance above 4 ohm, and it calls for over 50 W of amplifier power. Height is 105.5 cm, width 30.5 cm and depth 51.0 cm, and one speaker weighs 30.5 kg. Buyers choose walnut veneer or black high gloss.

Engineering and use context

Up top, the RP94 is a closed ribbon rated at 94 dB efficiency, working from about 2.5 kHz upwards with a moving mass of 0.01 grams and no transformer. Each woofer cone is a sandwich of two thin carbon layers on both faces of a 4 mm Nomex honeycomb core and weighs 5.5 grams. The patented motor contains no iron at all - four opposing neodymium ring magnets press the flux across two solid copper discs acting as pole pieces, reaching 1.1 tesla. Those copper rings also sink heat and cut voice-coil inductance to 0.04 mH, under 10 percent of a regular driver. In this standard version the tweeter magnet system is listed at 0.0040 mH. The crossover is wired in series rather than in parallel, so the drivers share one current path through the transition region. Coils are paper-insulated foil types vacuum-impregnated with resin, capacitors are arrays of small military-spec stacked-foil parts, and tweeter attenuation uses metal strip resistors. The cabinet is a heavily braced block of milled compressed wood with solid walnut inserts, styled after shapes first drawn by Franco Serblin. The tweeter chamber is vented and the bass section uses tuned ports. Built-in Ansuz Darkz T2S decouplers sit between each speaker and its ground cross plate, whose adjustable feet can rest on further Darkz discs.

Pairing

Børresen itself suggests the Aavik U-580 unity amplifier with Ansuz Speakz D2 speaker cable and Darkz T2 Supreme resonance control as matching parts for this model. Its modest power requirement leaves room for integrated amplifiers as well as separates.

Alternatives

The Børresen 02 Cryo Edition keeps this cabinet and driver layout but adds a three-day cryogenic treatment of all metal parts.