This is a nice simple sound meter indicator. Small enough to build directly onto a perf board and all of the components are quite common which will keep the build cost down.
“This project uses an LM3915 bar-graph IC driving two sets of ten LEDs for a 30dB range. The circuit is unique because it has an additional range of 20dB provided by an automatic gain control to allow it to be very sensitive to low sound levels but it increases its range 20dB for loud sounds.”
Sound Level Indicator
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Hi Alan,
I’m currently working on building this project, and I’m wondering if there’s an easy method to replace the microphone with an audio input? Let me know what you think.
Thank you!
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I wasn’t the creator of the project but yes that should work fine. You would need a pot though so that you can reduce the input to a usable level.
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hi ALAN, its awesome to get such sort of ready made circuit diagram;but am a bit puzzled with the components of circuits ;i mean how it works ? can u mail me abt the circuits working principal.Thanx Dude!