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Lm386 Audio amplifier

U-Lhan

Mar 11, 2017
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I used Lm386 as an audio amplifier, 9V , and when I check the output waveform it amplifies but it was clipped. I just copied the circuit diagram on its datasheet. How to fix this? Any advice there in making an audio amplifier with good sound quality ?
 

davenn

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Sep 5, 2009
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I used Lm386 as an audio amplifier, 9V , and when I check the output waveform it amplifies but it was clipped. I just copied the circuit diagram on its datasheet. How to fix this? Any advice there in making an audio amplifier with good sound quality ?

what is your signal source ?

bluejets explanation is the most likely
 

U-Lhan

Mar 11, 2017
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Thanks a lot that was very helpful. But how can I increase the volume without distorting the signal? Is it i am going to use better ic instead of lm386 ?
 

U-Lhan

Mar 11, 2017
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So what is the best thing to do to increase the volume without distorting the signal?
 

poor mystic

Apr 8, 2011
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Hi :)
Most designs use at least one more stage of amplification, depending on how much power is wanted at the output. I personally like DC amplifiers with long-tailed pair inputs and FET output transistors, but perhaps they're out of fashion by now...
 

davenn

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So what is the best thing to do to increase the volume without distorting the signal?

The 386 amp only requires a tiny signal to produce it's around 1 watt max output
 

U-Lhan

Mar 11, 2017
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The 386 amp only requires a tiny signal to produce it's around 1 watt max output
Okay thanks.. maybe i'll make it stereo so that it may sound louder. Oh before i forgot, Is it okay to change 0.047uF capacitor into 0.1uF capacitor? And i used all electrolytic capacitors is it also affecting the sound quality ?
 

Arouse1973

Adam
Dec 18, 2013
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Maybe your expecting too much from this little amplifier, thing is how loud is not loud enough :)
Adam
 

Audioguru

Sep 24, 2016
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Didn't you look at the manufacturer's datasheet of the LM386 amplifier?
With a brand new 9V battery its output is shown on a graph to be 6V peak-to-peak into 8 ohms which is 2.122V RMS so the output power is (2.122V squared)/8 ohms= 0.56W that is not very loud.

Our hearing's sensitivity is logarithmic so doubling the power (stereo instead of mono) sounds only slightly louder. 10 times the power sounds twice as loud.

An LM1875 amplifier IC produces 20W into an 8 ohm speaker when it is powered by 50V. It is in a case with a metal tab that you can bolt to a heatsink to cool it because it produces about 18W of heat.

An LM3875 IC produces 56W into an 8 ohm speaker when it is powered by 70V.

Some amplifier ICs are actually two amplifiers with opposing outputs to drive both wires of a speaker with about 3.5 times more power than a single amplifier using the same power supply voltage. They are called a "bridged" amplifier. Most car radio amplifiers are bridged so they can produce about 15W into a 4 ohm speaker when powered by the 13V car battery. Then all 4 speakers produce 60W.
 

Bluejets

Oct 5, 2014
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My wife uses a bluetooth speaker coupled to her phone.
Only 2w but drives me nuts with the volume.
 
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