Trying and failing to get Andrew Tuline’s “SoundMEMs peak ripple” working with one of these microphone boards:
I’m not having much luck. The microphone is seemingly unadjustable with the on board pot, as in it doesn’t seem to make any difference to it detecting audio or not.
The external pot I have wired up does make a difference. But it’s either making the lights change without the mic seeming to work properly (like noise on the mic signal line) or just not work at all with no amount of shouting at the mic being picked up.
Funny thing is I have an almost identical setup working, same mic same external pot. Difference is the arduino, I’m using a UNO this time and used a Nano last time.
Any help much appreciated, can’t find info on the mic board but I can tell you it has a LM393 chip on it.
This is driving me crazy, I’m about to try swap the UNO for a Nano, but that almost seems silly to me to think it’s making the difference.
I have tried wiring up the mic to 3.3v using AREF like stated in the code example and just straight into 5v. Both those worked on the Nano, neither on the UNO.
I have various sounds sensors and they have been horrible for this purpose. I don’t think they’re real ‘amplifiers’ per se. I had the best luck with the Sparkfun MEMS microphone.
@Danny_Evans It is not a problem with the board. This thing is a sound detector module. The pot on it adjusts the sensitivity of the detection threshold. It changes the DC bias on the electret microphone which does also change the amplification of the audio signal from the MIC but it is far from being a nice MIC pre-amp circuit.
@JP_Roy Sorry I meant by that that it appears to be a problem to get them working nicely with this code on an arduino.
I’m sure they are “working” Just not very well.
The onboard pots seem pretty poorly made. I think I busted one today by looking at it funny. Couldn’t get a steady variable reading from it on my multimeter. Kept jumping at once and would read differently without turning the pot on a couple of occasions.
I think I’ll try the MEMS boards and see how that goes.
Can’t believe they are cheaper on Sparkfun than AliExpress!
@Danny_Evans Nothing to be sorry about… I actually also bought that little module for a similar application a while back as it was dirt cheap and had an analog output. But I quickly discovered it was not very well suited as a Mic preamp.
I ended up gutting the electret mic out of that board and built my own little DC bias circuit and soldered that directly to a LM386 Audio amp modules (… another cheap audio module).
@Danny_Evans Any and all info can be fetched from within this forum, search for… “JP Roy + Xmas” and you will see posts starting in 2014 and you may follow the quite slow evolution of my Xmas tree project over the years. I still have more work planned for Xmas 2016, mostly 3D animations finally !!
With regards to the MSGEQ7, they are great little modules and I simply duplicated the circuit found in the datasheets as-is. The more tricky part was with the electret/audio amp circuitry, as I kept getting too much noise on the audio. I found a lot of the noise came from using the same PSU as the one used for switching the LEDS. Ultimately, I solved that by powering the audio circuit separately with a 9V battery. Unfortunately, I stored all my detailed notes, sketches and designs with my Xmas tree and can’t share any specific details until late this year… sorry !!
Hi @Danny_Evans , nice find indeed !!
However, with its fixed 20dB gain, you may need a small audio amp with adjustable gain (200 dB max). They are just as cheap about $1-$2… but then maybe not !?
