Bowers & Wilkins 801 D4

The 801 D4 is the flagship floorstanding loudspeaker in the 800 Series Diamond range — and the reintroduction of the 801 designation is a statement of intent. This is a model name with decades of history in professional and domestic audio, carried by loudspeakers that have defined reference standards in recording studios and listening rooms across the world. Bowers & Wilkins have brought it back because they consider the D4 generation worthy of that lineage — and having heard the 801 D4, we agree without reservation. Martins Hi-Fi is the second oldest Bowers & Wilkins dealer in the world, and this is the loudspeaker that represents the full extent of what the brand's engineering is capable of.

Diamond Tweeter and Solid Body Enclosure

The 801 D4's tweeter dome is machined from solid synthetic diamond — not diamond-coated, but solid diamond throughout. Diamond is the stiffest natural material available, and that stiffness ensures the tweeter dome maintains its geometry perfectly under the most demanding high-frequency signals, reproducing treble with a clarity and resolution that no metal or fabric dome can match. The tweeter is housed in a Solid Body enclosure — a precision-machined aluminium casting that eliminates diffraction and provides a mechanically inert, resonance-free mounting point. Above the main cabinet on its Tweeter-on-Top mounting, it operates in complete acoustic isolation from the drivers below — free from the cabinet-borne vibrations that colour the high-frequency performance of conventionally designed loudspeakers.

Continuum FST Midrange Driver

The midrange driver uses Bowers & Wilkins' Continuum cone — a woven material developed specifically to eliminate the characteristic colouration that the previous Kevlar cones introduced, a resonance that, once identified in isolation, could not be ignored. Continuum removes it entirely. The driver is mounted in a Fixed Suspension Transducer configuration — eliminating the conventional foam surround and the intermodulation distortion it produces — and housed in the Turbine Head, an all-aluminium enclosure whose ribbed profile is derived from fluid dynamics research. The ribs suppress internal standing waves; the aluminium construction ensures the Turbine Head is mechanically inert. It is decoupled from both the bass cabinet below and the tweeter body above, giving each driver its own acoustically isolated environment.

Biomimetic Suspension

The voice coil spider — the component that centres the voice coil in the motor gap — uses a Biomimetic Suspension design inspired by natural structures. Conventional spiders behave non-linearly at the extremes of their travel, introducing subtle distortion that robs the music of composure at high levels. The Biomimetic design maintains consistent behaviour across the full excursion of the driver, contributing to the 801 D4's extraordinary composure when pushed to the limits of its considerable dynamic capability.

Aerofoil Bass Drivers and Anti-Resonance Plug

The bass section employs Aerofoil profile cones — composite constructions whose cross-section varies in thickness from edge to centre, providing the precise combination of stiffness and mass that each point on the cone surface demands. An Anti-Resonance Plug is fitted to the rear of each bass driver, suppressing the back-wave energy within the motor system that undermines bass definition in lesser designs. The result is bass of a quality that matches the 801 D4's extraordinary midrange and treble — controlled, articulate, and extended to a degree that redefines what a domestic loudspeaker is capable of.

Matrix Cabinet

The bass enclosure uses Bowers & Wilkins' Matrix internal bracing — a lattice of interlocking aluminium panels bonded inside the cabinet walls, subdividing the internal volume and eliminating the panel resonances that introduce colouration into the sound of conventional box loudspeakers. The D4 generation brings an upgraded Matrix design with more extensive aluminium reinforcement than its predecessors — a further reduction in cabinet coloration that reveals more of the music and less of the enclosure.

Technical Specifications

Who Is It For?

The 801 D4 is for the listener who has decided that the best is the only acceptable standard — and who has the room, the amplification, and the system to match. It demands serious electronics and a room large enough to allow it to pressurise the space as it was designed to. If you are building a reference system without compromise, this is the loudspeaker from which everything else follows.

Buying from Martins Hi-Fi

Martins Hi-Fi has been in Norwich since 1968. Elizabeth Gould runs the business today, and we stock only brands we have heard properly and stand behind. As the second oldest Bowers & Wilkins dealer in the world, we have a relationship with the 800 Series that goes back to its earliest incarnations — and the 801 D4 is available to hear in our Norwich showroom. Dave and Chris can walk you through the full 800 Series Diamond range, discuss amplifier matching in depth, and arrange a private demonstration at a time that suits you.

Those also considering the range should explore the Bowers & Wilkins Nautilus — the ultimate expression of Bowers & Wilkins engineering — and the DB1D subwoofer for those wishing to extend the 801 D4's already extraordinary bass performance further still.

Contact us at info@martinshifi.co.uk, call 01603 627010, or WhatsApp on 07554 687137. You can read more about how we work on our Why Martins Hi-Fi page. We are at 85–91 Ber Street, Norwich, NR1 3EY.