No Sound Coming Out W/ Midi Options

[JOLTINJAKE]

hi, i have a mac set up with an Edirol midi keyboard and Cubase. when i try to record stuff with the midi keyboard, i see the green and red bars that show it has been recorded, but no sound comes out. ive done regular audio recordings, and that worked, so im really confused why theres no sound coming out even though i see that the midi has entered my computer. thank you for any help you can give!