music is playing you really don't hear it. Your using really small fans concealed in a dash. I really don't think it will be loud or noticeable. Most of the time you run your A/C don't you? So the noise of the blower will drown out the noise of the fans. i really don't think you need 2 fans though, infact, with the back being open like that, i am with drawing my opinion on the slots as well. Your board isn't anal like mine were it seems to over heat so quickly.