I visited our local bass guru and I asked him about some of the ideas I posted here. He told me not to do either one of them. a) I was going to add a 2x10 cabinet to my 1x15 combo. He said my combo was monaural and that the 2x10 would actually limit my sound - it isn't capable of handling anything other than mids. (It didn't have a tweeter nor two open slots at the bottom of the cabinet). The 2x10 would probably have blown out if I tried that. He said that only 2x10 cabinets have the highest failure rate of all cabinets. b) I was going to try doing a line-out to the FX return of a cheap 2x10 combo. He said that the signal would have been a really crappy and it wouldn't been very good. In the end, he recommended that I add another 1x15 cabinet made by Yorkville since the combo was designed to operate that way. If I got a new rig, he suggested it be bi-ampable (well documented at TB) with a 2x10 w/tweeter and a 15". The SWR Triad was also suggested. He also said that you can skimp anywhere except when you are purchasing speakers. Does anyone care to add their two cents while my brain is still digesting his comments?