555 Timer IC Musical Instrument

I have seen many posts about 555 timer IC and I worked with it in school, but we did not make a music whit it so I made one.List of parts is on diagram, I made box by myself,but you can use box from some old device, and I made some modification to circuit I aded a potentiometer before the line of buttons and resistors, there is a LED diode on output but it will not work if there is stereo conected.

I will post a test video about it, a picture is worth a thousand words.