These “bookshelf” subwoofers produce a wide range from 28Hz to 356Hz efficiently, only requiring a 800 watt amplifier. This small subwoofer isn’t just another unique design. Tom has implemented a new form of acoustic bandpass which allows the two 8-inch woofers to work best in the frequency range intended. This also significantly reduces coloration from harmonic distortion, resulting in a very pure recreation of the original source.