18W + 18W Stereo Hi-Fi Audio Amplifier (TDA2030)


2 x 18W Hi-Fi Stereo Power Amplifier based around two TDA2030 ICs. It has good input sensitivity, low distortion, good operating stability and full protection against overloads and output short-circuits. It can be used as a booster amplifier for existing small systems or to drive a second pair of speakers besides the ones already connected to the system. The board needs a symmetrical power supply of ±18Vdc/3A and can be connected to loads of 8 or 4 Ohm. Large heat sink is required for this circuit. Diagram shown below indicates only left channel. Make two circuits for for stereo version.

Picture of the project:

Picture of the project

Circuit Diagram:

Picture of the project


  • R1 = 22K
  • R2 = 680R
  • R3 = 22K
  • R4 = 1R-1w
  • D1 = 1N4001
  • D2 = 1N4001
  • C1 = 1uf-25V
  • C2 = 22uF-25V
  • C3 = 100nF-63V
  • C4 = 100nF-63V
  • C5 = 100uF-25V
  • C6 = 100uF-25V
  • C7 = 220nF-63V
  • IC = TDA2030

If it does not work:

  1. Check your work for possible dry joints, bridges across adjacent tracks or soldering flux residues that usually cause problems.
  2. Check again all the external connections to and from the circuit to see if there is a mistake there.
  3. See that there are no components missing or inserted in the wrong places.
  4. Make sure that all the polarized components have been soldered the right way round.
  5. Make sure the supply has the correct voltage and is connected the right way round to your circuit.
  6. Check your project for faulty or damaged components.

Technical Specifications:

  • Supply voltage = ±18Vdc/3A symmetrical (see text)
  • Current consumption = 3A maximum
  • Input impedance = 500K Ohms
  • Input sensitivity = 250 mV
  • Signal to noise ratio = 80 dB
  • Frequency response = 20 - 20,000 Hz ± 1 dB
  • Distortion = 0.5 % maximum
  • Load impedance = 4 - 8 ohm