Is it normal to have an orgasm from a subwoofer?

I'm a dude and I was in my buddy's car the other night listening to music. He has a really cool sound system and he has subwoofers that give it good bass. Anyway, we were listening to music and he got the subwoofer going during the song. It shocked me kind of at first but then as the bass and vibrations continued shaking my car seat and the car basically it started to feel really good. I just thought it was some good vibrations so to speak. The good feelings started to get better and better until I started to feel that familiar orgasmic feeling. I kid you not. My friend looked at me and asked if I was ok but had a weird smirk on his face. I just said yeah I'm doing great lol. I finally tapped out and just felt a release through my body but I didnt ejaculate. I think I experienced my first dry orgasm. Seriously, that orgasm was actually better than any regular penile/ejaculation orgasm I've ever had. I'm completely at a loss as to how vibrations from the bass of the subwoofer could actually get me off! It was amazing though. Now I want to do it again really badly and experience that feeling again. Any other guys ever experienced this or have any idea why I would have an orgasm from the vibrations generated by a subwoofer???