Напольная акустика — Børresen Acoustics Børresen 03 Cryo Edition

The Børresen 03 Cryo Edition is the deep-frozen variant of the 03 floorstander from Børresen Acoustics, the Danish maker whose 0-series also covers the 01, 02 and 05. The five-driver enclosure is the same as the standard 03, and the difference lies in a cryogenic process that every metal part of the speaker passes through before it is built.

Key specs that matter

Børresen states that the process increases conductivity by 6 to 8 percent, and it lists the magnet system inductance at 0.0038 mH. Each cabinet holds one ribbon tweeter and four iron-free 5 inch bass/midrange units. Quoted response spans 35 Hz to 50 kHz, sensitivity is 88 dB per watt, nominal impedance is 4 ohm, and Børresen advises more than 50 W of amplification. The enclosure is 124.1 cm tall, 30.5 cm wide and 58.0 cm deep, one speaker weighs 38.0 kg, and walnut veneer or black high gloss can be ordered.

Engineering and use context

The cryo cycle spans three days of 24 hours each - a controlled cool-down to cryogenic temperature, a hold at around -196 degrees C, then a slow warm-up back to room temperature so that no thermal stress builds up. According to the company, the crystal lattice of the metal compacts, alloying elements leave the grain structure and internal stress left from casting is relieved. Beyond this treatment the build follows the 03. Its RP94 ribbon, with a diaphragm weighing just 1/100 gram, takes over at roughly 2.5 kHz and has an efficiency of 94 dB on its own. The woofers pair honeycomb-core carbon membranes with motors that use neodymium rings and copper discs in place of iron. Signal division uses a serial filter in which woofers and tweeter carry the same current through the transition band, built from paper-insulated foil inductors and small stacked capacitors of military specification. The braced compressed-wood cabinet is veneered, the tweeter chamber vented, the bass section ported, and Ansuz Darkz T2S decouplers sit between cabinet and base plate. The cabinet shapes follow a line first drawn by the late Franco Serblin.

Pairing

Børresen names the Aavik I-580 integrated amplifier and Ansuz Speakz D-TC2 speaker cable as matching components for the 03 Cryo Edition. The low impedance and the modest power figure suit a single-box amplifier with good current delivery.

Alternatives

The Børresen 03 Silver Supreme Edition takes this cabinet further by replacing the copper pole rings in the woofer motors with silver ones.