Interesting. I wonder if he has ran into patent issues now that he is making for other people. I'm going to have to catch up with his builds!I just stumbled on Chris Hudlin's YouTube videos concerning his DIY rotary subwoofer builds. He's building a few of these for customers now and he seems to be tweaking the design as he builds new units. If you build this, some parts might go out of production and you would need to find suitable alternatives. Not a deal breaker.