The following is the list of parts required for a sound effects machine:
Arduino Uno (one unit)
2N3904 NPN transistor (one unit)
8 ohm speaker (one unit)
470 ohm resistor (yellow, violet, brown, and gold) (one unit)
4.7 kilo ohm resistors (yellow, violet, red, and gold) (four units)
Tactile pushbutton or toggle switches (four units)
SD module (DFRobot [PN:DFR0071]) or Arduino compatible (one unit)
Breadboard
Wires