I know bi-amping has been discussed a lot in here, and I did search a bunch of threads without finding what I'm looking for. I currently have one Avatar 4x10 cab and I'm looking into adding something for low end. Now I really like the range of the 4x10, however it starts breaking up on the lows whenever I try to play a 5 string through it. So I want to add either a 1x15 or a 2x12 to even out the low end. Do you think I need to bi-amp it? It makes sense that it'd be best to cut out some of the lows on the 4x10 and pass them to the 2x12 or 1x15, but I don't want to cut out the highs from those speakers also. It seems what I really would just need is a frequency filter on the 4x10 side. Now the PLX 3402 I have powering it does have a low pass filter at either 50 or 30 Hz, however I don't think it can do it for individual channels. There's this thing: http://www.qscstore.com/uf3.html which looks like it may be able to do it (Help me out Bob Lee ). Overall I'm getting a bit confused and could use some suggestions to make this rig work out. I'd prefer to get the 2x12 over the 1x15 because it would be more versatile if I had to use it by itself.