I am trying to make a sound sensor using a Raspberry Pi 3B. I would like it to be able to differentiate between a door knock and a phone ringing. When a sound is detected, i would like to light a green LED for phone and red LED for the door knock.
This device will be used for a person who is all but def so that they will know when someone is at the door or when the phone rings.
Any recommendations for decent microphone, other hardware and code (python) would be greatly appreciated. Let me know if i am asking to much of the Pi, python, or ???
I am relatively new to the Pi world, but not a total novice when it comes to electronics.
Hi @moose, Welcome and nice to meet you. Ah, let me see. I think you need a couple of hardware things to start off your project: (1) USB sound card, (2) microphone, (3) loudspeaker. I usually recommend USB UGreen sound card to newbies: (1) “AliExpress USB External Sound Card”: aliexpress.com/popular/external-sound-card.html. USB sound cards are usually both Widnows PC and Rpi friendly. In other words, you can start testing with PC Win10 and then move on to Rpi OS. – tlfong01 1 hour ago
For microphone, cheap ones are usually better than expensive ones. The following Q&A shows pictures of USB sound card, microphone, etc: “Identify which microphone is on which audio card using arecord”: raspberrypi.stackexchange.com/questions/105280/…. The above post contains a list of references where you can find microphone power amplifier such as MAX9812 which is good to do newbie experiments. Cheers. – tlfong01 1 hour ago
This is a link to the MAX9812 mic power amp: fr.aliexpress.com/item/…. Cheers. – tlfong01 1 hour ago
You may find the above references include the Rpi OS software utilities “arecord” and “aplay” for recording and play sound files such as mp3 which are compatible to both Win10 and Rpi OS. Arecord is for offline playing back and audio analysis. – tlfong01 6 mins ago
If you wish to record audio realimte, you might need to use hardware ADC (Analog to o Digital) converter such as MCP3008 etc and input the digital signals to Rpi cord is for offline playing back and audio analysis. If you wish to record audio realimte, you might need to use hardware ADC (Analog to o Digital) converter such as MCP3008 etc and input the digital signals to Rpi for audio recognition. If you only need to recognize, door knock, and phone ringing, the there are cheat tricks such as by time periods (door knocks, is usually shorter, or only two to at most 5 peaks etc). – tlfong01 6 mins ago
I know my above long winded comments are a bit overwhelming. In case you wish to know how a newbie like you is learning the stuff bit by bit, you might like to read slowly the following long story: “Detect [loudspeaker] current on Raspberry pi – rpo.org.forum, 2018oct17”: raspberrypi.org/forums/…. Cheers. – tlfong01 1 min ago Edit