Hello, I'm trying to design a sound to light circuit.
I found this:
https://www.electro-tech-online.com/threads/simple-sound-to-light.93961/?highlight=opamp
which is probably what you all will tell me I should use, but I was trying to make this as compact and cheap as possible, and that seems a little more complicated then what I was hoping for. And I don't even know what some of those parts are... like the "U1OPTO".
I have a working circuit, but I'm new to electronics and I'm confused why my circuit isn't working as well as I'd like it to.
Here's the circuit I've been using.
**broken link removed**
I had it working better at one point, but I was stupid and didn't write down the details. So the values I found to be best this time around are:
Rm = 1000Ω, C1 = 1 µF, Rin = 100Ω, Rf = 10^6Ω
It works, but the voltage outputting from the op amp seems low, and the mic isn't sensitive enough, which I suppose means the op amp isn't applying enough gain, right?
According to my understanding if I make Rin 100Ω and Rf 10^6Ω the gain should be 10000, and if I make Rf = 10^9Ω the gain should be 10000000, but it seems to be maxing out at around 10^6Ω.
I tried putting a NPN transistor on the output and it didn't seem to do diddly! Can someone tell me what I would need to do to use a transistor? If I ever get the mic sensitive enough I would really like to be able to run more than 10 LEDs (the max output of this op amp is 200mA and the LEDs run at 20mA max).
I originally had a resistor in line with the LEDs too, like this:
**broken link removed**
(which I thought was necessary since I don't want to kill my LEDs with the "gained" output of the op amp) but when I removed the resistor the LED was brighter, which I still don't really understand... something about the op amp and the mic taking voltage?
I know there are probably many things I'm doing wrong, as I haven't had any training is circuit building, other than what I've given myself. I would very much appreciate any help anyone has to offer. But hey, be nice, I'm a newbie.
Thanks in advance, ~Paul.
I found this:
https://www.electro-tech-online.com/threads/simple-sound-to-light.93961/?highlight=opamp
which is probably what you all will tell me I should use, but I was trying to make this as compact and cheap as possible, and that seems a little more complicated then what I was hoping for. And I don't even know what some of those parts are... like the "U1OPTO".
I have a working circuit, but I'm new to electronics and I'm confused why my circuit isn't working as well as I'd like it to.
Here's the circuit I've been using.
**broken link removed**
I had it working better at one point, but I was stupid and didn't write down the details. So the values I found to be best this time around are:
Rm = 1000Ω, C1 = 1 µF, Rin = 100Ω, Rf = 10^6Ω
It works, but the voltage outputting from the op amp seems low, and the mic isn't sensitive enough, which I suppose means the op amp isn't applying enough gain, right?
According to my understanding if I make Rin 100Ω and Rf 10^6Ω the gain should be 10000, and if I make Rf = 10^9Ω the gain should be 10000000, but it seems to be maxing out at around 10^6Ω.
I tried putting a NPN transistor on the output and it didn't seem to do diddly! Can someone tell me what I would need to do to use a transistor? If I ever get the mic sensitive enough I would really like to be able to run more than 10 LEDs (the max output of this op amp is 200mA and the LEDs run at 20mA max).
I originally had a resistor in line with the LEDs too, like this:
**broken link removed**
(which I thought was necessary since I don't want to kill my LEDs with the "gained" output of the op amp) but when I removed the resistor the LED was brighter, which I still don't really understand... something about the op amp and the mic taking voltage?
I know there are probably many things I'm doing wrong, as I haven't had any training is circuit building, other than what I've given myself. I would very much appreciate any help anyone has to offer. But hey, be nice, I'm a newbie.
Thanks in advance, ~Paul.