50W Power Amplifier Circuit

The following diagram is a 50W power amplifier circuit diagram based on a pair of power transistors MJ2955 and 2N3055. The transistors are usually used for OCL amplifier, the output audio quality is very good, you should buy the transistors which have good quality . Using heatsink on the transistors is a must.

Here the Schematic diagram:

PCB layout:

This amplifier require dual output power supply (+, ground and -). Use this power supply circuit:

For maximum performance, use 3-5 Ampere transformet with 24V secondary output.
You may use 5A Diode bridge or 4 pieces of single 5A diode.

About Audio Amplifier
An audio amplifier is an electronic amplifier that amplifies low-power audio signals (signals composed primarily of frequencies between 20 - 20 000 Hz, the human range of hearing) to a level suitable for driving loudspeakers and is the final stage in a typical audio playback chain.

The preceding stages in such a chain are low power audio amplifiers which perform tasks like pre-amplification, equalization, tone control, mixing/effects, or audio sources like record players, CD players, and cassette players. Most audio amplifiers require these low-level inputs to adhere to line levels.

While the input signal to an audio amplifier may measure only a few hundred microwatts, its output may be tens, hundreds, or thousands of watts. More explanation about power audio amplifier can be found at wikipedia.org

This is a video tutorial about how to a very simple audio amplifier based on the LM386 amplifier chip. It can be built for less than $20 (or might be less than $8 in some countries) and used to amplify any low level audio signal including a guitar, bass or mp3 player.

Watch the video: