I have an Energy es10 sub for my house. I have had it for ??????????6 years or so, and I never really was that impressed with it from the day I brought it home. Anyway, it finally blew up(speaker) so I decided to go into the garage and get one of my car stereo woofers I have sitting in the garage from my days when I had lots of toys. I simply removed the speaker from the sub box and replaced it with a punch 10 inch sub I used to use in my car many moons ago. After I removed the energy, I couldnt believe how cheap that thing looked. Tiny magnet, thin metal construction, just looked like a 10 dollar speaker. To my surprise, the punch speaker sounds 100% better. The synergy would pop or rattle anytime I really cranked up some good hard rock and i basically just turned it way down when listening to music. I can crank it up now with the punch. What is up with that?? You would think it would be worse, not better.