PSB's New Flagship Speaker
Canadian speaker company PSB has majored in high-performance affordable speakers, with its tiny Alpha, introduced in 1992, becoming on of the best-selling speakers of all time. Designer Paul Barton (above), however, has been working on a flagship PSB speaker, which he demmed at the Lenbrook suite at the Hard Rock Hotel. Yet to be named, the new speaker will cost a still-affordable $4500/pair and spearheads a new line of six models to be introduced in the second quarter this year.
No fasteners of any kind are visible on the gracefully curved enclosure: black-anodized aluminum extrusions form the front and back, and top and bottom surfaces of the MDF cabinet, with the drivers mounted to a sub-baffle beneath the aluminum. Tweeter is a titanium-dome type mounted beneath the midrange unit, while each of the three 6" woofers is loaded with its own ported sub-enclosure. The result, says Paul, is a speaker that goes louder and deeper more cleanly than his Stratus Gold of a decade ago. The lower-frequency drivers use cones made from felted natural fibers laminated with fiber-glass to give the requisite combination of lightness, stiffness, and self-damping. Copper shorting rings on the voice-coils and an aluminum ring on the rear of the magnets help reduce midband THD to <0.1% at 96dB spl!
The placement of the woofers on the front baffle and the crossover filter slopes for each, as well as the midrange unit, was calculated so that the speaker is virtually immune to the usual response "floor-dip," due to destructive interference between the drive-units' direct sound and the reflection of that sound from the floor. It is relatively easy to arrange for the floor dip from the midrange unit to occur below its passband and that from the lowest woofer to occur above its passband, but optimizing the behavior of the other two woofers must have been tricky, to say the least.