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Simple LM386 audio amplifier

video Simple LM386 audio amplifier
The song is:
Infected Mushroom
semi nice

FAQ:

Q: The sound sUxx0rz, fix it!
A: Can't, since there are barely any parts.

Q: How do I add volume control?
A: Either in series with the speaker (volume) or between pin 1 and pin 8 (gain)

Q: Why is there a 7805?
A: To conserve power, you can go without it if you feel like it.
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lworm2 years ago
Hey Kirbsome! I got a question. I'm some kind of new in that kind of projects ... So why do other users use Capacitors for their amps, what does that change?
Best Regards
Kirbsome! (author)  lworm2 years ago
Capacitors can do several things. In amps like this one, it's usually
  • To block DC from going through the speaker while passing signal, thereby conserving power.
  • To smooth out power going into the amp, thereby reducing a common humming noise.
  • Combined with a resistor to make a high / low pass filter, thereby making a tone control circuit.
The reason I didn't use any capacitors for this amp is because I tried using as few parts as possible, but if you want better sound quality I highly recommend them.
Hope this helps!
lworm Kirbsome!2 years ago
Hey Kirbsome!
Thank you very much - that helped alot, that was a great reply!
Have a nice day,
Lenwo
codestroy73 years ago
To anyone out there :)
Some of my music has heavy bass, but the amplifier cannot output it properly due to lack of power. Is there a way in which I can "precharge" the amplifier so that it won't lack power when a heavy bass comes?
Kirbsome! (author)  codestroy73 years ago
Well, it might also be the speaker (small speaker = no bass) but you could always try adding a low-pass filter
Actually when i use DC adapters capable of delivering 5 volts at higher amperes, the bass is good, that's why i'am sure that its not my speaker. Since i want to create a pocket amplifier, adapters should not be considered as power source, so i want to know if i can create something like precharging the amplifier so that it will be ready for a bass comes.

Thank you for a reply i'll try putting a low-pass filter. i'll just post here what ever will happen to my amplifier :))
Kirbsome! (author)  codestroy73 years ago
As stated:
There's a lack of bass when there's a lack of power.
The only solution would probably be using some bigger batteries.
Maybe a DC-DC converter? I don't know.
But I do want to know how it works out for you :)
DaHandy3 years ago
Could you please post schematics for this? Thanks!
Kirbsome! (author)  DaHandy3 years ago
Sure.
LM386 amp.bmp
I want to build this into something ( a music led box) i already made, but it has a 12 v power supply. Can i just add this to the same supply or do i need to do something else?
Kirbsome! (author)  Johnny Lavabo3 years ago
It should work just fine at 12v, you can use the 5v regulator if you want to.
wasteroo3 months ago

This makes for a terrible amplifier, but it would be pretty good at keeping a very tiny cup of coffee warm

husmen4 months ago

Hi, is there any alternative of LM386 that I can use?

manugp1 year ago
I also have a Muvo
Kirbsome! (author)  manugp1 year ago
Aren't they great?
dritonsyla1 year ago
hei guys this is didnt work for me, coz is a noise, i dont have regulator butt im using adapter 6v, can u explain me what is the problem ?
dritonsyla1 year ago
hei guys this is didnt work for me, coz is a noise, i dont have regulator butt im using adapter 6v, can u explain me what is the problem ?
Can you tell me a way to solder the mono jack, or what the little parts are for similar to what you did at the beginning of this video? Please and thank you.
samalert1 year ago
I am building 12v car LED strip sync with music using TIP31
Now i built it but those dont give enough Volts to lit the LED's bright, i read that one needs amp to increase the Voltage to TIP31 now constructing your circuitry help me do it ?
Kirbsome! (author)  samalert1 year ago
I'd like to help you, but I don't really understand you. What are you trying to do here?
hey what electronic device carries the lm 386 chip? what other chip could i use instead and where to get it out of.......
Kirbsome! (author)  astrogotnext1 year ago
I'm not sure I fully understand you here.
hey where can i find a lm386 chip, in what device or can i use a substitute,b-c i have a tm555a could i use that?
Kirbsome! (author)  astrogotnext1 year ago
LM386-es can be found in a wide variety of devices, from phones to R/C cars.

If you're unsure about your chip's specs, try to find a datasheet.
khubi2 years ago
pls how do i add a volume controll knob
Kirbsome! (author)  khubi2 years ago
Please read the other comments.
this is great bro keep it up, i love your innovation
Kirbsome! (author)  macsonservices2 years ago
Reading this made me happy :)
this is great bro keep it up, i love your innovation
mak242 years ago
hey Kirbsome....

i tried the circuit on a breadboard first and although i was getting the output it was tooo noisy... i mean... i pulled out the jack from my ipod earphones and connected them to my droid.. and used the wires to emulate the circuit on a breadboard.. but on a breadboard the output was too noisy... the song itself was not identifie\able over the jittery noise after sometime.
Kirbsome! (author)  mak242 years ago
what do you mean by "...used the wires to emulate the circuit..."
I want to help you out here, but I don't really understand the question.
mak242 years ago
@kirbsome..

how do you deal with the noise, i constructed the same on a breadboard and found too much noise
Kirbsome! (author)  mak242 years ago
If you mean noise like interference from outside sources, I'd suggest putting it in a grounded Faraday cage.
If you mean distortion from the amp itself, that's just it's sound.
Remember:
There are barely any part in this thing, so the sound quality is bound to be crap.
wampastompa2 years ago
I just made my second one of these :)
nice! (Y)
codestroy73 years ago
to Kirbsome.

i placed a high-pass filter to remove some of the very low frequency bass, now it sounds good. the next i'll try is removing the filter and applying a dc-dc conversion i think it will work but i'll just try to be sure. :) i'll just inform you what will happen next :)

btw. why did you suggested putting a low-pass filter? low-pass filter will remove high frequency audio right?
Kirbsome! (author)  codestroy73 years ago
Low-pass filters do not "remove" high frequencies, but rather dampen them.
I recommended a low pass filter since you said there's not enough bass.
Or did I misunderstand something here?
roeggebear3 years ago
ok i really want to make a amp but i can't find the amp chip in my broken sound system there is three chip that got same number as pins but it isn't a lm386 it is like a fm388 i think from top of my head im new to this stuff
Kirbsome! (author)  roeggebear3 years ago
So you're telling me you don't have a 386, good to know.
Tell me the exact part number and i might be able to help.
it is f4558
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