This Web based spectrum analyzer with ESP32 8-64 channels uses a ESP32 DEVKIT V1 and only 4 external components. Using the switch, you can select the number of bands you want to display on the webinterface 8,16,24,32 or 64 Uppon first boot, the wifi manager will kick in asking your WIFI credentials. If it doesn’t, you can force the manager to start by holding the mode button while rebooting.

This is an open source project, all schematics, software and building instructions are available for you.…

I did a side to side comparison of a Analog based Spectrum analyzer and a FFT based one.
Based on performance, can you replace your double MSGEQ7 setup with a ESP32 and FFT library?
I compared both versions with a line input and a Microphone input and combined all in a video.
To compare, I used the same code( Sketch) but both with it’s own plugin to get the frequency information. So, one uses a FFT libary and the other uses my existing hardware with two MSGEQ7 and Frequency board.…

In this video tutorial I am sharing some of the methods I have used now and in the past regarding the sampling of audio signals. It shows you three methods:
1. Sequential sampling
2. Interrupt driven sampling
3. I2S (IIS) driven sampling

This is an open source project, all schematics, software and building instructions are available for you. Use it, change is, heck even sell it. It’s ok but if you do one or more of the above, please give me credit by linking back to my channel.…

Januari 2021 was the time that “The practical Engineer: Emiel Noorlander” joint forces with Arjan from AB Customs by unleasing a build challenge into the world.
They challenged their viewer to build something using a few marked words:
Frikandel ( a dutch hotdog), Hands Free, 12 Volts.

Whatever is being build, useful or not, if it is related to the words above, it can enter the challenge.
So that is what I did. I Build something completely useless to enter this competition.…