B&W Prestige Monitor 1 (PM1)
PM1 is a compact loudspeaker that offers an extremely high-quality performance. It features a new tweeter design, and a cabinet unlike anything previously constructed by Bowers & Wilkins.
The PM1 loudspeaker features several technological advances as well as advanced application of core Bowers & Wilkins technologies. Thereâ€™s a new tweeter design, a fresh implementation of a Kevlar cone, and Matrix bracing. There is also the continued implementation of the principles of purity and simplicity plus approaches learned from the development of the 800 Series Diamond.
Carbon Based Tweeter
This design takes the already high performance of Bowers & Wilkins aluminium domes to a whole new level. The Carbon Braced Tweeter uses a ring of ultra-thin wound carbon fibre to brace the tweeter dome, and as a result raise the break up of the aluminium dome to around 40KHz, which has a dramatic effect on the audible frequencies below 20kHz.
Outweighing a standard dust cap in terms of performance, the Anti-Resonance Plug minimises sound overhang through a reduction in cone break up. The voice coil bobbin flexing is dampened to mellow the upper frequency response of the driver.
We carry out exhaustive listening tests rigorously assessing the performance of each component until we find the optimum component for each position in the circuit. Fine-tuning by ear is only possible if the crossover is simple and the section of the crossover that perhaps benefits most from our policy of listen-and-learn is the part handling the signal for the tweeter. In most Bowers & Wilkins speakers, it is carried by a single, ear-chosen component that preserves the very finest detail.
Kevlar has been Bowers & Wilkinsâ€™ cone material of choice since 1974, and with good reason. Not only does it deliver a cleaner sound, it can do so to a wider group of listeners. The distinctive yellow cones are found on almost all Bowers & Wilkins loudspeakers.
Unique to Bowers & Wilkins, MatrixÂ interlocking panels take cabinet bracing to the ultimate level. With powerful bass drivers trying to shake the cabinet and high air pressures inside trying to make the panels flex and blur the sound, this three-dimensional honeycomb structure reinforces the cabinet at small intervals and in every direction. Offering a dramatic cut in the level of cabinet coloration, Matrix allows you to focus on where the performers are, rather than being aware of where the speakers are.
Tweeter on Top
Bowers & Wilkinsâ€™ tweeter on top technology has two benefits. It avoids the situation with normal cabinet construction, where sound waves from the tweeter not only radiate towards the listener but also travel along the baffle surface towards the cabinet edges. It also allows its time-alignment with the midrange driver to be finely adjusted so the two outputs add perfectly in phase through the crossover region.
Bowers & Wilkinsâ€™s Flowport minimises turbulence in the same way as a golf ball. Dimples on the surface generate tiny eddy currents over which air can flow smoothly, reducing turbulence, and improving performance. This is because if turbulence occurs as the air moves in and out of the port, youâ€™ll hear extraneous noise and, as you turn the volume up, the bass wonâ€™t be as tight and well timed as it should be.Â
Nautilus Tapering Tubes
Not all sound generated by speaker drive units is good sound. The kind that emerges from the back of a working driver, into a conventional box cabinet, can bounce around and make a mess of the good sound coming out of the front. Bowers & Wilkinsâ€™ trailblazing Nautilus speaker found a way around boxes. Tapering tubes filled with absorbent wadding soaked up the wayward sound energy and reduced resonances to an insignificant minimum.
Preventing mechanical vibration from the bass cabinet reaching the tweeter leads to a much cleaner, sweeter high frequency performance. For the 800 Series Diamond, weâ€™ve adopted a synthetic gel to cushion the tweeter better than ever before. Not only that, weâ€™ve also isolated the tweeter assembly from the tube and mounting behind, which reduces external interference to virtually nil.
Nautilusâ„¢ tube loaded tweeter with carbon fibre reinforced aluminium dome
KevlarÂ® fibre cone bass / midrange Flowportâ„¢
Description 2-way vented-box system
Drive units 1x 25mm (1in) reinforced aluminium dome high-frequency
1x 130mm (5in) woven KevlarÂ® cone bass / midrange
Frequency range -6dB at 42Hz and 60kHz
Frequency response 48Hz - 22kHz Â±3dB on reference axis
Dispersion Within 2dB of reference response
Horizontal: over 60Âº arc
Vertical: over 10Âº arc
Sensitivity 84dB spl (2.83V, 1m)
Harmonic distortion 2nd and 3rd harmonics (90dB, 1m)
<1% 110Hz - 22kHz
Nominal impedance 8Î© (minimum 5.1Î©)
Crossover frequency 4kHz
Recommended 30W - 100W into 8Î© on unclipped programme
Max. recommended 0.1Î© cable impedance
Height: 331mm (13in)
Width: 191mm (7.5in)
Depth: 250mm (9.8in) cabinet only
293mm (11.5in) including grilles and terminals
Net weight 9.3kg (20.5lb)
Finishes Cabinet real wood veneers: Mocha Gloss
FS-PM1 Floor stand
Height: 620.5mm (25.6in) excluding spikes
W idth: 268mm (10.6in)
Depth: 300mm (11.8in)