Elwood
Blues
my understanding (mis-understanding?) was the idea was to get a solid thump with rapid decay. When I have messed with it that's what I have found was cool. You can drive a hard bottom and not leave a lot of clutter in the air. This takes a bit more that the std Fender foam though to get it to work "right". Sure not for everyone on every tune. I believe Duck Dunn used this on some tracks we all love.