Finding the right microphone for a wearable device

Projects General Guidance
1

Dear Arduino-fellows,

For a project, where I'd like to build a wearable device that measures a couple of environmental parameters, I am currently searching the best microphone to use. I've searched for one that fulfils the following requirements:

  1. The microphone must be tiny enough to pack it to a casing for convenient wearing
  2. The microphone should have a relatively large support base and it should be possible to source it from large ecommerce shops like mouser.
  3. The sensitivity should be good enough to track most of the environmental noises.

I have ended up buying following mics:

  1. The MEMS SPW2430 from adafruit:
    Adafruit Silicon MEMS Microphone Breakout - SPW2430 : ID 2716 : $4.95 : Adafruit Industries, Unique & fun DIY electronics and kits

and:
2. Max4466 Elektret mic:
https://www.ebay.de/itm/Max4466-Elektret-Mikrofon-Verstärker-Einstellbar-Modul-Amplifier-Gain-Breakout/183968256551?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

To sum up, both kind of work but I'm undecided which is the best one to go with. The elektret mic with a max4466 seems to be more sensitive. For absolute Sound pressure level readings, both mics need a calibration I guess, where I need to buy a sound calibrator.

I'm just interested in how you have realized your projects or what you think.

2

Sound calibrators are very expensive. There is a program called RTA (Real Time Analyzer) that is free to less then $100 depending on options. It runs on windows only however it does a great job and is fast. I use an external sound card with it and I have a reference microphone to validate the setup. You will have to build a pseudo anionic chamber and you will need an amplifier and sound transducer (speaker, hence the reference microphone). This response is to help you get started in solving your problem, not solve it for you.
Good Luck & Have Fun!
Gil

3

mbobinger:
Dear Arduino-fellows,

For a project, where I'd like to build a wearable device that measures a couple of environmental parameters, I am currently searching the best microphone to use. I've searched for one that fulfils the following requirements:

  1. The microphone must be tiny enough to pack it to a casing for convenient wearing
  2. The microphone should have a relatively large support base and it should be possible to source it from large ecommerce shops like mouser.
  3. The sensitivity should be good enough to track most of the environmental noises.

I have ended up buying following mics:

  1. The MEMS SPW2430 from adafruit:
    Adafruit Silicon MEMS Microphone Breakout - SPW2430 : ID 2716 : $4.95 : Adafruit Industries, Unique & fun DIY electronics and kits

and:
2. Max4466 Elektret mic:
https://www.ebay.de/itm/Max4466-Elektret-Mikrofon-Verstärker-Einstellbar-Modul-Amplifier-Gain-Breakout/183968256551?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

To sum up, both kind of work but I'm undecided which is the best one to go with. The elektret mic with a max4466 seems to be more sensitive. For absolute Sound pressure level readings, both mics need a calibration I guess, where I need to buy a sound calibrator.

I'm just interested in how you have realized your projects or what you think.

I personally prefer condenser (electret) mikes for their high fidelity and great sensitivity. For size though, the MEMS mike is a better choice. If the MEMS mike isn't sensitive enough... and a preamp!

4

krupski:
I personally prefer condenser (electret) mikes for their high fidelity and great sensitivity. For size though, the MEMS mike is a better choice. If the MEMS mike isn't sensitive enough... and a preamp!

Thank you for your responses! I am currently experimenting with condenser and MEMS typ mics. As mentioned before, the condenser type ones offer a better sensitivity but eventually a MEMS with a preamp will do as well. I'll dig more into it.

Could you eventually recommend a DIY solution, which preamp fits for a MEMS?

Thank you!