I tried playing my 6-string geetar through my Carvin R600 bass amp with the tube channel cranked and the bass turned way up post-distortion and I found that I could create wild subharmonics by playing double stops on the guitar. If I played various intervals on the high notes of the guitar I could make clear, deep bass lines come up out of nowhere, and I could even go lower than a bass. For example, playing a major 3rd through distortion produces a note 2 octaves below the root. Bigger intervals produce higher subharmonics and smaller intervals produce lower subharmonics. If I cranked up a minor 2nd, I'd probably have to have some speakers reconed. I tried it on my bass too, but the lower harmonics seemed to low to be safe or usable. I imagine it would sound bad ass with some subwoofers. Does anyone else do this or have a use for it?