The iSub is a $99 USB subwoofer — a speaker that produces powerful bass sounds — that looks more like a jellyfish than a multimedia component. Its 6-inch woofer belts out 20 watts of bass down to about 40Hz. (However, Power Mac G4 users shouldn’t get too excited about the iSub: it’s designed to work only with the latest generation of iMacs, the ones with slot-loading CD/DVD drives.)
Harman Kardon built the iSub to complement the new iMac’s built-in speakers, which the company also designed. The built-in speakers have an eight-octave range and alter their output when the iSub is plugged in, divvying up the aural workload to create the best sound.
Apple’s Audio Extension 1.3 provides full support for the iSub, and when we plugged and unplugged it from an iMac DV Special Edition, the iMac quickly recognized the speaker’s presence (or absence) and adjusted sound accordingly — without any pause in the music coming from the computer.
Macworld’s Buying Advice
Will the iSub make it any easier to understand exactly what Bob Dylan is singing? Probably not. But it’ll make listening to whatever it is he’s singing a more pleasurable experience. — JONATHAN SEFF