You can make a strong comparison between these two hp's. With the Alpha Pads, the MD is now voiced a little closer to the he500 albeit the overall tone is still just a touch darker.
But like the he500, the MD is smooth and effortless across the spectrum never giving you "extra" than what the recording offers. These are not bass head cans because there is no bass added when the recording doesn't have it. But when the material has a hard bass line the MD will throw it down and with authority, accuracy and smile inducing punch.
Given the price difference, I'd pick the MD for sure. If the he500, were say only $300...I'd still pick the MD.
Oh gawd... Best spur of the moment purchase.ever me thinks. I have an 18v jds cmoy bb that with my hm601 should really drive these well. The hm601 is powerful enough to drive my dt880s unamped )n it drives em well) still me so excited