8 Watt Audio Power Amplifier Schematic


Here is the schematic for an 8 watt audio power amplifier. This amp can be used as a simple booster, the heart of a more complicated amplifier or used as a guitar amp. It is very small and portable unit and can be powered through 12V battery. I built the circuit on a Vero Board and had to add extra inductors, capacitors and resistors to prevent oscillation.

Circuit diagram:

Circuit diagram


  • R1 = 47K
  • R2 = 2.2R/1W
  • R3 = 220R/1W
  • R4 = 2.2R/1W
  • C1 = 100nF-63V
  • C2 = 10uF-25V
  • C3 = 470uF-25V
  • C4 = 2000uF-25V
  • C5 = 100nF-63V
  • IC1 = LM383
  • SPKR = 4ohm/8W


  1. IC1 must be installed on a heat sink.
  2. C1 is for filtering and to prevent oscillation and should not be omitted.
  3. The circuit can be built on a Vero Board, universal solder board or PC board, the PC board is preferred.
  4. The circuit draws about 880Ma at 12 V.
  5. By swapping the values of R2 and R3; you can turn this amplifier into a guitar amp with no preamp required.
  6. If you can't find 2000uF, then replace C4 with a 2200uF unit.
  7. If you add a 0.2uF capacitor in series with a 1 ohm resistor to the output you can prevent oscillation of the circuit under certain conditions.