The Yamaha YST-SW100 is a super woofer system that incorporates Yamaha's Active Servo Technology. This technology uses an internal amplifier to virtually eliminate electrical resistance in the speaker coil, combined with a specially tuned enclosure and Helmholtz resonator to strongly reproduce low bass frequencies.
The HIGH-CUT frequency control knob adjusts the cutoff point from 40Hz to 140Hz and above.
The unit supports voltages of 110/120/220/240V AC at 50/60Hz.