Introduction: Low Frequency Audio Amplifier Using the LM386

Picture of Low Frequency Audio Amplifier Using the LM386

The integrated chip LM386 is a low power audio frequency amplifier requiring a low level power supply . The IC is designed to deliver a voltage amplification of 20 without external add-on parts. But this voltage gain can be raised up to 200 (Vu = 200) by adding external parts.

soo today i am going to show you how to make a  low frequency audio amplifier using the LM386 .

Step 1: Getting Started






Have fun building your amp.. :)

Step 2: Things You Need....

Picture of Things You Need....

This is an a cool audio amplifier and it is easy to build. Only few components are required....

1- LM 386 semiconductor (IC)

1 – 100 uf polarized capacitor

1- 220 uf polarized capacitor

1 – 10 ohm resistor

1 – 10K var. 

1- 10 uf polarized capacitor

1 – .047uf ceramic capacitor

1 –  3.5mm stereo jack male


 *  Wires
*   voltage sourse (  5 - 12  v  )
*   soldering rod and wire
*   wire stripper
*   Cutter

A speaker of your choice for output.

Step 3: Volatge Source

Picture of Volatge Source

voltage source i used here is a nokia mobile charger..

ACP-12E Input AC 100-240V/50-80Hz/180mA
OUTPUT DC 5.7V/800mA

Step 4: Circuit DIAGRAM

Picture of Circuit DIAGRAM

circuit is not designed by me.
it is one of 1000.. which i found from google .

very simple.. very easy..    :p

Step 5: Connect the Circuit As Shown in Diagram:

Picture of Connect the Circuit As Shown in Diagram:

I suggest building the circuit on a bread board first. It’s much easier to troubleshoot and find errors and you can easily experiment with different components.
You’ll also learn more as you can see what each component does by removing it or changing its value.

Solder components carefully to ensure there are no shorts, also ensure all connections are made at all points.
Be sure to double check connections to make sure a connection isn't left out. 

Step 6: Finish.. :P

Picture of Finish.. :P

use screw driver to change resistances which changes  volumes of ur song .

now test ur system by connecting ur audio device to male jack...


enjoy  :)  :D :P



TheChristoph99 (author)2015-11-17

how low can the voltage go?

AkhilJ6 made it! (author)2015-10-22

Im getting high distortion.
And when i hold the power supply wire it decreases

sreejithextreme (author)2015-10-06

please tell me where to get the audio jack online

osdoyi made it! (author)2015-08-15

I have made it. But lm385 is overheating. What could be the problem ?

KevinP8 (author)2015-01-26

Hi. can you make tutorial video.


obwonkonobe (author)2014-12-18

hi, i made the exact circuit, and it does work, but i'm having a major issue, it noisy. it almost sounds like some one crumpling newspaper on a microphone. i removed the 10uf capacitor between pins 1 and 10, and that seamed to help, is there anything else that may be causing the issue? thanks in advance!

obwonkonobe (author)obwonkonobe2015-01-11

how would I filter the psu?

aalejo (author)obwonkonobe2015-01-11

Filter the psu

obwonkonobe (author)obwonkonobe2014-12-18

sorry, pins 1 and 8

DearN (author)2014-12-26

Hi, I would like to amplify a 100-200 mv pulse to 5v DC. The frequency of the pulse would vary between 20-600 per second. At lower frequency the pulse is 100-200 mv, So I would like to amplify it to 5 volt. But at higher frequency the pulse goes upto 30-50 volts. So I would like to maintain the pulse to 5 volts at all frequencies So I need the schematics for it or the desired changes in the above schematics. Plz PlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlzPlz

rimar2000 (author)2014-02-05

Very interesting, thanks for sharing.

Er Varun Goyal (author)rimar20002014-02-06


its my pleasure sir,.....

Can i use a 3 watt 8 ohms speaker??

cooltech12 (author)2014-03-01

easy and cool . thanks for sharing.

samuraijack (author)2014-02-10

pretty cool.

added to my collection.

will try to make.

thank you.

anytime sir. .. and thanx to you too .

About This Instructable




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