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How to make an audio amplifier circuit to power a speaker? Answered

I have a 4 Ohm 90 Watt Speaker and I want to be able to play music from my phone on that speaker. I know I need to give the audio signal more power so that it can be used with the speaker, but how do I do this? I have found other circuits on Instructables that accomplish the same task but they are all for much less powerful speakers and only produce less than 1 watt. Any solutions? Thanks



3 years ago

Your best option will be to use one of the integrated circuit (IC) amplifiers that are well established..

As a start i suggest you go for an LM386.


with a few extra components this makes a reasonable low power amplifier that should drive your speakers.

There are other higher powered IC amps around but the 386 is cheap and easy to assemble.


3 years ago

Your going to have to search Ebay (And trust your not buying Garbage)


Most online stores like SparkFun and Adafruit will only carry lower powered Amps. You could also try a Car mono amp but it will be a bit more expensive !

Either way Check the Spec's. Most amps will support 4-Ohm