The Devil wears Prada (The band)?

I was wondering how TDWP got their sounds from the effects they use. Their main effect pedals is the Ibanez Tube Screamer (TS9). I don't know about any of you other guitar players out there but I've tried the TS9 at a guitar center and when I try the palm mutes it doesn't come out..it felt like a total blues pedal. How can TDWP get these sounds out of that pedal??? Do they mix the Tube Screamer with their Mesa Boogie distortion?