i found this on an interview with the drummer Joakim Jonsson :
what's a D-Drum trigger? is this some kind of device for cheating?What drum gear do you use?
I have a Pearl kit, 1 bass drum and 4 toms. I have two snare drums; one piccolo and one wood. Sabian cymbals: Ride, Hi-hat, 2 crashes, 3 chinas, 2 splashes. Any sticks and a DW 5000 double pedal. I´m using a D-Drum 4 trigger with trigger mics on the bass drum and the snare. I wish I could afford a new drumkit. I´m pretty tired of it.