Полочная акустика — QLN The Signature

The Signature is a stand-mount two-way loudspeaker with bass reflex loading from the Swedish maker Qln. Its shape descends from the original Qln One, with a slanted front baffle and a sloped top in the form of a truncated pyramid. The cabinet is built entirely from the company's Qboard material, and the current version is offered in Walnut Matte or Walnut Burl Piano, listed in North America at USD 24,000 and USD 27,000 per pair respectively.

Key specs that matter

Qln rates the low end at -3 dB at 38 Hz. Sensitivity is 87 dB SPL for 1 W at 1 m, measured over the 100 Hz to 10 kHz band, nominal impedance is 8 ohm, while Qln asks for amplifiers delivering 50 to 250 W RMS. The tweeter uses a 25 mm textile dome, a broad roll surround and an AirCirc motor. Below it sits a 184 mm mid-woofer with a Kevlar cone. Each cabinet measures 448 mm high, 280 mm wide and 480 mm deep and weighs 31.0 kg, which is heavy for a speaker meant to sit on a stand.

Engineering and use context

The mid-woofer is a proprietary unit developed together with the Danish driver specialist Scan Speak. It uses an under-hung magnet system with a copper ring in the motor. The angled baffle lines the tweeter and woofer up in time, while the small surface area of the sloping top is intended to suppress baffle effects and standing waves inside the enclosure. Qboard construction is meant to remove structural resonances from the acoustic chamber. The reflex port flares like a trumpet at both ends to keep air turbulence low. Inside, the constant impedance crossover is hardwired and uses non-inductive capacitors, flat foil inductors and precision metal film resistors - 20 W types in the woofer section and high-power parts for the tweeter - while the capacitors are bypassed with copper film types, and the coils are baked to avoid internal component resonances. Each cabinet carries one pair of silver-plated copper WBT Nextgen posts, which rules out bi-wiring. An earlier Signature, now listed by Qln among its discontinued models, was a smaller 12.1 kg design.

Pairing

A stable load and the recommended power window make solid-state integrated amplifiers and moderately powered valve designs both workable choices, and the weight of each cabinet calls for rigid, well-anchored stands.

Alternatives

The Qln Prestige One is a lighter stand-mount model from the same company for those who want a smaller cabinet.