Yamaha Yst-sw80 Subwoofer

Yamaha Active Servo Technology
Exclusive Yamaha system allows the amp and the speakers to work together to boost the power of a stereo speaker's output. Instead of an ordinary woofer unit, the speaker has a Helmholtz Resonator that intensifies the sound waves inside until they are output as much stronger sounds. Total impedance(resistance to current flow) has to be zero, so the amp's circuitry produces negative impedance, canceling out the speaker impedance. The result is bass sound that is very powerful.
Negative Output Impedance Amplifier
In order to reproduce deep bass tones, speaker impedance must be zero. This is accomplished by using the negative output impedance amplifier precisely matched to the Helmholtz system.

Anti-Magnetic Shielding
The speaker can be located near a TV or video monitor without distorting the picture.

Phase Control
Allows you to adjust speaker phasing to best suit the room's acoustic conditions and different sound source.
Adjustable High Cut Filter

You can set the cut-off frequency from 40 to 140 Hz, at the position where the subwoofer output best matches the other speakers, so the overall sound is balanced and natural.
2-Way Binding Speaker Terminals

Banana Plug compatible and permits the use of a variety of speaker wires and connectors.
Auto Power Switch

Subwoofer will turn itself on automatically when it senses a music signal. It will also turn itself off automatically shortly after the music signal stops.

Specifications
Adjustable High Cut Filter 40 - 150 Hz Continuously Variable Output Power
Built in 85 Watt Amp.
Frequency Response - 23 Hz - 170 Hz
Dimensions (W * H * D) 9-15/16" * 19-1/8" * 14-7/16"
Shipping Weight 30.8 lbs.

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