I have been kicking around the idea of adding a guitar sub woofer to my live rig. i go back and forth from it being totally redundant to it maybe being awesome. we have a good bassist. the places we play have pretty good sound systems. seems like i could send less lows to my 4x12 and the sub would take over those frequencies. i play a 7 string in drop a, using a helix lt. it would mean going down to just the 4x12, i woudn't bring the sub and the 2x12. its not anything i could really test out before buying so i was just curious. i just think that our doom sections and breakdowns would be extra killer if everything rumbled but i could also see it being a huge waste. thanks!!!