Bookshelf Speakers — Psb Imagine B50

The Imagine B50 is the two-way bookshelf speaker of PSB's Imagine series, the range the Canadian company introduced alongside the T54 and T65 towers. The Imagine models inherit technology from the top Synchrony and the PWM wall-mount series, including woven carbon fibre cones, mass-loaded rubber surrounds and fourth-order crossovers, and the B50 is designed for stereo use or for the rear channels of a matched Imagine system.

Key specs that matter

Its tweeter is a 25 mm titanium dome, ferrofluid damped and driven by neodymium, paired with a 133 mm (5.25 in) woven carbon fibre woofer, crossed at 2200 Hz with a Linkwitz-Riley fourth-order network. On-axis response is 45 Hz to 23 kHz (+/-3 dB) and 60 Hz to 20 kHz (+/-1.5 dB), with a -10 dB point at 36 Hz. PSB quotes 85 dB sensitivity in an anechoic chamber and 87 dB in a listening room, an 8 ohm nominal load that dips to 4 ohms, and a 20 W to 150 W amplifier window. The cabinet measures 171 x 300 x 251 mm (W x H x D), at 5.3 kg each, or 11.9 kg for a boxed pair.

Engineering and use context

PSB mounts the woofer above the tweeter, and the steep fourth-order crossover keeps the two drivers in phase through the transition. For that reason the company recommends stands of about 60 cm, placing the listener's ear at 91 to 99 cm. The woven carbon fibre cone combines stiffness with low mass, and the mass-loaded surround damps edge resonances. The low-resonance MDF cabinet is extensively braced, and a rear slot port extends bass output. The aluminium trim and bevelled cabinet edges follow the look of PSB's PWM in-wall range. Dual gold-plated five-way binding posts with jumpers allow bi-wiring or bi-amping, and the grille is removable. It is offered in black or white satin. The Imagine models were measured and tuned at Canada's NRC laboratory, where Paul Barton has worked on PSB designs since the 1970s.

Pairing

The higher in-room sensitivity figure lets integrated amplifiers and AV receivers of 40 W or more drive the B50 in rooms up to about 20 m2. For home cinema, PSB's AST-25 stands and a matching Imagine centre build a surround layout, and a subwoofer takes over below the point where the flat range begins. The rear slot port means the cabinet should stand some 20 cm or more from the wall behind it.

Alternatives

PSB's Imagine T54 turns the same driver technology into a compact tower with a 102 mm midrange and two 133 mm woofers.