NHT SA-3 subwoofer amplifier: 250 watts @ 6 Ohms Continuously variable low pass filter 35-150Hz High pass filer - 65, 80, 100, 125, 150Hz Adjustable phase - 0, 90, 180, 270 degrees Here's a review: http://www.hometheaterhifi.com/volum...subwoofer.html I am the second owner. The amp is in good shape cosmetically, but does have a few small scratches on the bottom of its faceplate. I do not have the original box, but will pack very well as well as double box. It's the perfect amplifier for integrating a passive sub into a system. List $750, Sell $300 + shipping from 14620.