Some of the most recent threads mention fairly powerful amps -- 200 Watts and even 500 Watts. Yet I find that the 100 Watts of my GK combo is more than enough to drive my bass into feedback, even with a magnetic pickup. How do you guys make use of the more powerful amps? To put it another way, how far away does your amp have to be when you are playing in "loud" situations? Any other tricks? There are situations where I would not mind being louder, such as when backing up a big-band, but I see no point in getting a more powerful amp if I can't use the power that I've got.