In my previous post I mentioned the Yamaha YSP-4000 soundbar. The Digital Experience phoned me the other day, and I have completed my sound-setup with the addition of the YST-FSW150 subwoofer from Yamaha:

The 130 watts subwoofer compliments the soundbar and produces rich sound (and fits perfectly into my TV-cabinet). Yamaha’s Advanced Yamaha Active Servo Technology (Advanced YST) is a unique system in which the speaker and amplifier work together to cancel out impedance so as to achieve perfectly linear motion in the speaker unit. Advanced YST helps to ensure the highest levels of sound pressure and overall performance.

Yamaha engineers introduced two proprietary technologies (the Negative Impedance Converter and the Yamaha Air Woofer) which combine into one interdependent system in which speaker and amplifier are combined in a closed “Active Servo” loop.

The FSW150′s imaging capabilities are incredible: Imagine sitting in the front row at the symphony. Close your eyes and visualize the placement of the members of the orchestra. The ability to reproduce this spacial quality of sound is known as imaging. Speaker size is one factor that can drastically contribute to imaging accuracy. Advanced YST speakers are small enough to have excellent imaging characteristics, yet still accurately reproduce tones from the very low bass of a pipe organ to the highs of a triangle and cymbals.

If you want to get all the technical details explained, read this article.