Quantity   Component name
1 × PS/2 computer keyboard
1 × ATMega 328-P or Arduino with SD capability
1 × LM317 adjustable voltage regulator or any voltage regulator that will give you 3.3V
1 × SD card
1 × dual op-amp I'm using NJM2068SD
1 × speaker(s)
1 × 5V power supply up to 12V would be acceptable
1 × various resistors, capacitors, bits and pieces See the schematics and pictures for details