Teensy 4.0 Sound from Electret Bob to FFT

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MSO

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Hello! I just purchased the 4.0 and I was looking to do some FFT on live audio. I currently have a microphone that produces a 1.25V biased 2V peak to peak signal which I have been using with a MSGEQ7 and Teensy 2.0++. I would like to cut out the temperamental middleman and do it in software.

I understand that the ADC is still being worked on, but I wanted to ask if there are any alternatives for a mic BOB or if I would be best just waiting until an ADC appears? Thanks for any help you can provide!
 
A good suggestion, I'm hoping to avoid additional hardware, so waiting looks like the best option for the time being. Thanks for your help.
 
That looks like a great option. I don't need it to be a particularly clean signal, but it still seems like it does what I need. Thanks for your help!
 
An additional option is to use MEMS microphones which often communicate directly via I2S or SPI.

There's a good description in this document https://www.st.com/content/ccc/resource/technical/document/user_manual/88/5d/3e/6d/9c/ae/42/de/DM00187403.pdf/files/DM00187403.pdf/jcr:content/translations/en.DM00187403.pdf about the options.

This thread looks at some of the practicalities of MEMS for Teensys. https://forum.pjrc.com/threads/57697-Need-help-MEMS-mic-with-Teensy-3-2-and-or-audio-shield?highlight=mems+i2s

And this one looks at using multiple MEMS microphones https://forum.pjrc.com/threads/58937-Teensy-4-0-I2S-(no-Audio-Shield)-4-MEMS-microphones-working-only-2?highlight=mems+spi

Have fun!
 
More great information! Thank you. I thought i2s was a higher level system, but it looks like little i2s BOBs may be just as good as the analog one I have.
 
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