Sunday, April 22, 2012

Stereo OTL Audio Amplifier

The following diagram is the circuit of Stereo OTL Audio Amplifier. It based on IC circuit, so the circuit looks simple. You can use IC LM379,LM377,LM378 for this amplifier project.

2x6W Stereo OTL Audio Amplifier circuit diagram

Refer to the table, maximum voltage supply for IC LM379 is 28V, it will will deliver 4W/channel. For LM377, maximum Vcc voltage is 18V single supply and delivers about 2W/channel. While for LM378, use maximum 24V regulated DC power supply and you will get 3W hifi audio power per channel.

Use heatsink on the IC to prevent overheating.

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

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:

1 comment:


Nice Circuit.....
Thanks buddy......

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