Hello, new member here. I am a guitar player (don't start throwing things...I have never even made a bass player joke before... except that one about how many bass players it takes to...well, never you mind that one) and I am getting more into bass. I recently purchased an SWR Basic Black combo online based on a memory of one a friend has. It is 120W 1-15" with a tweeter crossed at 5K. If you plug in an extension cab (8 ohm) the power increases to 160W (total 4 ohm load) for increased headroom and more SPL when needed. I am interested in putting a new speaker into a ported 1-12 that I have that is currently housing a Celestion G12K-85. A fine guitar speaker, but it can't handle significant low end without distorting in very unpleasant ways. So, here is the question...what 12 can I put in that cab, if any, that will compliment the 15 and tweeter in the BB? I thought about cutting a new baffle in the 112 to house 1 or 2 10" speakers, but the baffle is dado jointed into the body of the cabinet, so I am stuck with the 12" baffle. I would assume that there is a reason that bass players usually use 10's and 15's and tweeters most often and don't use 12's unless it is a small cab or combo for smaller gigs. In my relatively few searches of cabinets I haven't seen a 12 and a 15 used together ever. I would rather not buy another cab if I can avoid it and just get a (hopefully cost effective) 12 that will augment the 15 and tweeter. Any and all thoughts welcome.