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Picture of LM386 Audio Amplifier
I wanted to design an audio amplification circuit for a future project so i just wanted to design this one for now so i get an understanding of how it works. This is a very basic circuit that you can find all over using an LM386 integrated circuit i got from RadioShack.
 
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Step 1: Obtain Parts

Picture of Obtain Parts
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All Components can be found at RadioShack.

Multipurpose PCB with 417 Holes
5-15 Volt DC power supply (4 AA or 1 9v Battery)
8 Ohm Speaker
Audio Source e.g. iPod
8-Pin Retention Contact
IC1    IC                           LM386 Audio Amp IC
R1     Resistor               10 Ohm
R2     Resistor               1K Ohm
R3     Potentiometer     10K Ohm
R4     Resistor               10 Ohm
C1     Capacitor             220 Micro Farad
C2     Capacitor             10 Micro Farad
C3     Capacitor             220 Micro Farad





Step 2: Place Components

Picture of Place Components
Arrange components the best you can using the wiring diagram. i placed them as close together as i could, but it may be easier to spread them out a little more or breadboard this circuit first.  I highly suggest breadboarding first just to get a feel of the arrangement, prior to soldering.

Step 3: Observe Diagram

Picture of Observe Diagram
Look through the wiring diagram to see what components need to be connected to what prior to soldering.  This is a basic wiring diagram, one of a hundred I found online, very basic. The one i used was from this website http://www.rason.org/Projects/icamps/icamps.htm.

Step 4: Solder Components

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Solder components carefully to ensure there are no shorts, also ensure all connections are made at all points.

Step 5: Clean Up and Test

Picture of Clean Up and Test
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Trim component leads and clean solder joints. Be sure to double check connections to make sure a connection isn't left out.  Hook up a 5-15 Volt DC power supply, your audio source, and 8 Ohm speaker and test it out.  Be sure to ground out the audio sources audio low line and ground out the speakers ground wire to the circuits ground.
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ClaudeG20 days ago
Can i hook up a sub to the output?
SreehariM made it!25 days ago

There is one mistake in the above circuit diagram.

Pin 5 is missed out and that is causing a lot of noise problem.

Here is the corrected figure.

-Sree

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I cant open the pic where is pin 5 connected to?
ClaudeG27 days ago
What should i do about pin 5 of the lm386 im hearing littke noise

Yes that is causing all the noise problems.

I have uploaded the corrected circuit including the connection to pin 5.

-Sree

SreehariM25 days ago
JohnB710 months ago

Where is a good place to buy capacitors and resistors, every time I google the specs of a capacitor or resistor they all look way different

tclayton JohnB728 days ago
Look up "joe knows electronics" on amazon. He sells kits that have all standRd sizes of caps all labelled and organized in bags , saves all the shopping around
tclayton JohnB728 days ago
Look up "joe knows electronics" on amazon. He sells kits that have all standRd sizes of caps all labelled and organized in bags , saves all the shopping around
mgrandi2 made it!1 month ago

That's the best configuration I've worked out. It sounds nice!!

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mbenavides1 year ago
Just wondering but i got a lot of distortion with this amp, how did you clean it up?

Tantalum cap (10 - 22 uF) across the power rails. Watch polarity on the cap.

sladejas2 months ago

I built this and it works much better than the default version on the TI datasheet. If you are experiencing distortion on the output (either audible or noise on the O-scope), add decoupling caps to the power rails. A 10 - 22 uF tantalum cap from power to gnd (watch polarity of the cap) cleans up the signal very well . Try it if you are getting noise!

nils_pan2 months ago

hi krmartin, i made it and working fine in 3 volts 4.5 volts also, thanks .....

nils_pan2 months ago

hi krmartin, i made this but unfortunately not working, i haven't used R3 Potentiometer 10K Ohm bcoz due to sortage not available locally, can i skip it or use 10 var...

diygeek0072 months ago

pretty simple circuit.good instructable. thank you :)

asimobot2 months ago
Hey, im bout to build this and im new to this kind of thing. when u connect the power output how do u connect both negative and positive to one wire

Quick question, and hopefully not a stupid one. How do I connect the audio input to this circuit? What kind of cord should I use? I have tried using a 2-wire cord and grounded the black cord, using the red as the input. That gave me some sound with lots of garbage. I spliced a set of earbuds and have a red, black, and green wire. Would this work? Please somebody help!

hi I was wondering if this would work with 2 speakers for left and right or just the one speaker????? If it would work for 2 speakers does anything change or everything stay the same????? would really like the help.

You can do with single output. Take single output and attach to stereo jacket.

For audio wire

Left side - circuit: signal-signal twisted together and ground

Right side- jacket: signal to left pin, signal to right pin jacket and ground to ground pin of jacket

You need audio wire and stereo jacket, ask to electronics vendor what is the ground pin of the 3 the other 2 are indifferent signals

Build 2 circuits and input L & R to individual circuits each having their own speaker.

pbardolet1 year ago

I've built the amp, and the music can be heard through the speaker, but in a very low volume, like if it's not being amplificated. Can anyone help me with that? I don't know what's happening.

Thanks.

Adjust you input potentiometer.

vinu mystify8 months ago

where is the pot in the circuit?

its R3, but i dont think it is in his build

16401012416 months ago
ricardov17 months ago

Cool, it really works, but i have a doubt about the components and about calculating scaling, Could you help me?

apuzari7 months ago
Worked like a charm!!!
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shekzz.rock7 months ago
Can I connect 2 8 ohms 3 watts speaker to dis amp..?
erik4048 months ago

Is it possible to swap the speaker for a mono jack output and connect the circuit to a mixing desk or even a audio input on a soundcard?

gpfanatic erik4048 months ago

I think so. Important Rout of this circuit is low how should to be and Rin audio card is high as usual

gpfanatic8 months ago

In this project is lacking output impedence versus speaker inductive component. In parallel to speaker is needed a RC circuit to balance inductive component of speaker. If you need to understand more on audio amplifier ask for my electronics website in PM

ktomar11 year ago
Which volts capasitors used in this.. ?
gpfanatic ktomar18 months ago

16 V works fine

Any capacitors with larger volts that power source voltage.

Cruzer_AU made it!8 months ago

Worked Great!

Now to make a PCB.

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gpfanatic10 months ago

The TDA2002. Look at the jackets. You can connect anywhere

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if i had an ipod how would you connect it to this amplifier?

You should find a jacket and audio wire with adapter. I have used jacked for in and out. You should find It to electronic workshop

gpfanatic10 months ago

I have done third projec in rason.org projectst. My LM383 was broken so I
have gone for TDA 2002 and It is works perfect, it is equivalent. So I
have got 7 W for speaker. The LM383 works fine for low power. If you
look data sheet you see the high distortion for 1W, but TDA 2002 works
fine even for 5-6W. In add remember LM383 is obsolete

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