The circuit generates sound in different tones when the buttons connected between pins 2 and 1 made with the ne555 timer are pressed. The capacitors connected to the tonal buttons of the voices are identified on the schematic with 5 buttons and the same connection shape as the capacitors available.
The capacitor values are indicated on the schematic but you can change the capacitor until you find the desired sound that you can use at any value. An 8ohm 0.5w 1w speaker can be used on output pin 3.
