What Yamaha keyboard do you have? The reason why I ask is I have a Yamaha DX7. When I hooked up my JV1010 the sound of the JV1010 is not the same as when I use Roland synth or controller. It has more life when I use Roland module with Roland synth. The JV1010 has more sounds and expandability than the X5DR. I do have Korg X5 keyboard and my JV1010 sounds better than using it with my Yamaha DX.