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I am doing a classic LED - sound reactive project. The only thing that is bothering me is that my electret microphone (MAX4466 from adafruit) is clipping, and it is because the maximum gain of this microphone is 125dB. Usually it is enough, but for not for my project.

I need to put the microphone inside of a drum (kick drum), and the signal clips every time I hit hard on the drum. I need to find a way to reduce the microphone's sensitivity even more. I thought about the following solutions:

-Put something in front of the microphone to attenuate the sound

-Unsolder the electret microphone, and put another one that has a higher SPL

-Maybe change the resistance of the adjustable gain to increase the maximum gain (Instead of the 10k to 100k Ohm, I solder a higher resistance)

I know that the difference between the maximum and minimum gain will stay the same. With a microphone that detects sound from 25dB to 125dB, lets say I attenuate sound, it might detect 45dB to 145dB. In my case, I don't care about the lower sounds, I am only looking for the loud BOOMs :)

I looked everywhere on the Internet, but everyone wants a better sensitivity, and I am looking for the opposite.

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  • \$\begingroup\$ The MAX4466 from Adafruit has adjustable gain, have you tried to adjust — i.e. lower — it actually? \$\endgroup\$ – user59864 Jun 11 '17 at 19:30
  • \$\begingroup\$ Yes it is set to the lowest sensitivity, and it is still not enough \$\endgroup\$ – Lalous Jun 11 '17 at 19:44
  • \$\begingroup\$ You need to find out if it is the amplifier or the microphone itself that is hitting its limits. Electret microphones are usually rated for a maximum sound pressure level. Your drums could easily exceed the rating of the microphone. You would use an oscilloscope connected to the microphone itself to see if its output is distorted. \$\endgroup\$ – JRE Jun 11 '17 at 19:45
  • \$\begingroup\$ If you don't mind modest fidelity then I've made carbon granule microphones using battery carbon (back in the day.) It might actually be insensitive enough for you. Today, you'd probably use activated filter carbon from an aquarium store. This link, books.google.com/…, shows you almost how I did it (though I used metal washers.) But this video shows another way: youtu.be/uAnlmoei_Co \$\endgroup\$ – jonk Jun 11 '17 at 19:47
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    \$\begingroup\$ @Muze: Correcting errors in a question is fine. Changing correct things ("electret microphone") to nonsensical things ("electric microphone") is not OK. Try to be certain of your own words before correcting some one else's words. \$\endgroup\$ – JRE Apr 4 at 7:39
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I would just wrap the microphone in foam tape or get a really thick foam cover and turn up the gain. I know it is not the electrical way of doing it, but this is why they use fussy booms to take out all the background noise.

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