As Tumblr Creatr Josh Lafayette shows us, double the keyboards means double the tunes. With the Citi® Double Cash card, you can earn cash back not once but twice. Earn 1% when you buy and another 1% when you pay for your purchase. Learn more here.
Doubling keyboards may double the tunes, but it halves the quality of the tunes, and makes it much more difficult for the player to play the songs.