I'm willing to bet he's using two keyboards because "from what it appears" he's utilizing 2 different instrument sounds.., something you'd normally do with two keyboard and the appropriate 2 tier keyboard stand, but this guy is using two roll carts side by side (which is really got to be uncomfortable on the back after a while.
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GEAR: Yamaha MOXF-6, Casio MZX-500, Roland Juno-Di, M-Audio Venom, Roland RS-70, Yamaha PSR S700, M-Audio Axiom Pro-61 (Midi Controller). SOFTWARE: Mixcraft-7, PowerTracks Pro Audio 2013, Beat Thang Virtual, Dimension Le.