Just playing around with my 1st TL experiment. It's ghetto, but sounds terifik for what it is. I have a cheap Walmart Regent HT-391 surround sound. I dropped the 5.25" subwoofer into a 5.5" cardboard tube I snagged from work 8'6" long. I believe that makes a 33Hz 1/4 wave. Once upon a time I had a TP roll glued to the cone for added mass experiments, so I tore it off so the black paper coating came off a little. I can't believe how loud and low the rear of the tube is VS how loud the driver end is... I wish I could do an 18' 22" pipe in my car for an IB3 22"! The camera is bad, sounds really distorted, but it's actually very clean and clear. I didn't do the 1/3rd-1/5 way in mounting, it was just a free experiment... so the high resonances are LOUD. http://www.youtube.com/watch?v=zQ5VY_DSdXw&feature=channel_page http://www.youtube.com/watch?v=FMlTlpA9H34&feature=channel_page