When You’re Ready to Get Serious About Your Hardware – The PDP Concept is a Logical Choice. Designed in California by Drum Workshop for optimal playability, the Concept Series Double Pedal is a boutique-inspired machine thats quick and responsive. The pedals design is outfitted with a dual chain concentric drive system, smooth cast extended footboard with integrated needle bearing hinge, single post auxiliary pedal, telescoping linkage with universal joints, and an offset toe clamp.