Bookshelf Speakers — B&W (Bowers & Wilkins) 805 D4

Bowers & Wilkins builds the 805 D4 as the small two-way monitor of its 800 Series Diamond, the fourth generation of a line first launched in 1979 and developed at the company's research facility in Worthing. It is the only stand-mount in the current 800 Series and shares its tweeter technology and cabinet construction principles with the 804 D4 and the larger towers above it.

Key specs that matter

A 25 mm diamond dome tweeter works with one 165 mm (6.5 in) Continuum cone bass/midrange in a vented-box system. Frequency response is 42 Hz to 28 kHz (+/-3 dB), extending to 34 Hz and 35 kHz at -6 dB. Sensitivity is 88 dB at 2.83 V/1 m, nominal impedance is 8 ohms, and B&W lists 50 W to 120 W of amplifier power into 8 ohms on unclipped programme. Second and third harmonic distortion at 90 dB stays below 1% from 90 Hz to 20 kHz and below 0.3% from 120 Hz to 20 kHz. The cabinet measures 440 x 240 x 373 mm and each speaker weighs 15.55 kg.

Engineering and use context

The diamond dome combines low mass with very high stiffness, which pushes its first break-up mode far above the audible band. Its housing is the Solid Body Tweeter-on-Top pod, machined from one aluminium block and isolated from the main enclosure, with an elongated tube-loading chamber behind the dome. The Continuum cone uses a composite construction meant to avoid the abrupt change of character that ordinary cones undergo when break-up begins. The D4 generation introduced the Reverse-Wrap cabinet, which curves the side panels towards the rear and frees a dedicated compartment for the crossover, isolating its capacitors from air pressure inside the enclosure. Internal Matrix bracing, an anti-resonance plug in the drive unit and a dimpled Flowport complete the construction, and the speaker terminals were upgraded for this generation. Standard finishes are gloss black, white, satin rosenut and satin walnut.

Pairing

The 805 D4 is not a difficult load, but its impedance dips to around 4.6 ohms, so an amplifier with a solid power supply matters more than its rated watts alone. Bowers & Wilkins specifies a maximum cable impedance of 0.1 ohm. The dedicated FS-805 D4 stand places the tweeter at seated ear height and is designed to lock to the cabinet.

Alternatives

The 805 D4 Signature is a later version of the same stand-mount with a revised crossover mounted on aluminium spines that also act as a heatsink.