I’m trying to create a proof of concept vibration headset “for the deaf” (mainly for videogames where spatial awareness from sound cues is important) for a University electronics project. I’ve attached a circuit diagram, (which will later have an output to vibration motors to vibrate when left or right sound is detected). I also would like to preface this with the fact that I’m not an electronics student, and I’m doing an electronics class as an elective. So I apologise for my inevitable ignorance. Essentially I am trying to get my arduino to read whether the audio is playing from the left or from the right. Using the set up I have, I was playing youtube videos which separate left and right audio (speaker tests).
I was really excited to see that I was getting the offset I needed (in order to read the negative voltages from the audio signal). I do get a reading from both my left and right inputs, but the issue is that both these readings only come from when left sound is playing (see attached). Reading my left port, will get the jumps when there is left sound playing, and the flat line when right sound is playing. This is also what happens when I read from my right port as well. I would have expected something like the peaks to happen when right sound is playing, and the flatline when left sound is playing. This is an issue because both ports simultaneously get some feedback when there’s left sound playing, and both flatline on right sound. If there’s no sound at all, it’s a flatline as well, so I can’t think of a way to determine whether right or left sound is playing.
Is there something I’ve done wrong? Or is there something I’m missing that will connect all the dots? I’d appreciate any input! I’ve tried some problem solving with perhaps using the same ground or voltage supply for both sides is causing what I’m seeing. So I tried to connect the right input with a 9V battery instead of using the arduino power supply, but I see similar results. Perhaps it has to do with my ground configuration? I connected all 3 grounds to separate ground pins on my arduino, but perhaps they’re all connecting to the same ground on the board and are therefore connected? I’m not sure.