Hi Buck:
I don't know what the difference is between the two but I DO own the KN3000. It is outstanding and I use it with a Roland E-20 to gig with. You might want to try the Technics website - they have all the boards on there and you may find specs that can help you. As for sound comparison, can't help you out as I've never heard the 2000. The 3000 would take your breath away!!!
HAPPY HOLIDAYS!
Camy