That's all well and good, Mac, but it doesn't explain the noticeable lack of low mids. Bose are anything BUT flat. That's not necessarily a BAD thing, it's those frequencies that are the hardest to dial in just right in a room. Bose takes them pretty much out of the picture.

There's an interesting comment on the Bag Sub page:

Sometimes the frequency range of the BagAmp is not deep enough, and you need stronger bass response. Keyboards, drums, bass guitar, soundtracks, DJ material, backing tracks can all contain demanding low frequency sound that requires a powerful low bass reproduction system.

I would have though that list pretty much covers EVERYTHING, so it basically means you HAVE to get the sub, too! Unless you are an acoustic guitarist that LIKES having no 'thump' or 'knock' when he needs it