This is a great concept and it has 100% shown me how tone deaf I am!!
Crack the code (Open source)
You slept at work and got locked in. To get out you need to disable alarm, because you can't remember it. Luckily you recorded the code sound on your phone. Play the sound of code and match it in the panel.
You can use this game as little musical instrument. The " * " changes octave the sounds are played.
This game is also useful to develop a musical hearing.
You can play it using your keyboard:
" * " is - and " * " on num pad
" # " is + and "/" on num pad