I have an electric piano but I don't have the power supply. It has a barrel connector with a negative tip, and wants 12 VDC, 1.5 A.

I have a power supply that is 12 VDC, 2.67 A, but it has a positive tip.

Is this supply sufficient? Can I modify my power supply in any way allowing it to meet the specifications? Sorry, I don't know much about circuitry and I'm hoping someone would be able to help.