Напольная акустика — Psb Alpha T20

The Alpha T20 is a passive tower speaker from PSB Speakers of Pickering, Ontario, Canada. It is built for both stereo and surround use, and PSB names the Alpha C10 as the matching centre channel for home theatre systems. The design follows the tuned port bass reflex principle with a rear-firing port. The Alpha Series itself dates from 1991, when it was first designed and built in a small Canadian town around the idea of affordable speakers focused on performance, drawing on research by founder Paul Barton at the Canadian National Research Council. The current generation was rebuilt with new custom drivers and a new crossover.

Key specs that matter

PSB quotes 36 to 21,000 Hz within 3 dB and 54 to 20,000 Hz within 1.5 dB on axis, 54 to 10,000 Hz within 3 dB at 30 degrees off axis, and a low-frequency cutoff of 28 Hz. Anechoic sensitivity is 88 dB against 90 dB in a typical room, and impedance is 8 ohm nominal and 6 ohm minimum. Recommended input is 15 to 120 W, with 60 W program rating, and the filter hands over at 2,500 Hz. Each cabinet measures 170 x 825 x 243 mm (W x H x D), holds an internal volume of 27.0 litres and weighs 11.9 kg. Finishes are Black Ash and Walnut.

Engineering and use context

Two 5.25 inch woofers carry the bass and midrange. They use textured polypropylene cones, which PSB says limit distortion and breakup, along with rubber surrounds and dual-layer voice coils. Above them sits a 0.75 inch dome tweeter of black anodised aluminium, cooled by ferrofluid, driven by a neodymium magnet and mounted in a front waveguide. The crossover is an acoustic Linkwitz-Riley L4 filter. The enclosure uses specially designed MDF with tuned wall thickness and strategic bracing to control resonances and standing waves, and the rear port is 64 mm in diameter. The cabinet is wrapped in a woodgrain vinyl finish, and the acoustically transparent grilles attach magnetically, leaving a clean front with no visible fixings. The slim frontal width keeps the tower narrow, which PSB presents as a way to fit substantial output into a compact footprint.

Pairing

Speaker cables connect to a pair of gold-plated five-way terminals. For a multichannel setup PSB points to the Alpha C10 centre, and the Alpha range also includes the Alpha S8 and Alpha S10 subwoofers.

Alternatives

PSB also makes the Passif 50, a tower model with a 6.5 inch woofer and an 8 inch passive radiator.