Hey folks. I am fascinated by using components the wrong way to achieve nefarious ends (as I’m sure the rest of you are), and I am really keen on getting a lightbulb compressor module to work.
I’m not an engineer (I don’t have a degree at all, really - I’m just a grease monkey) - and I have done a lot of research and tried to work it out on my own, but I think I might make more progress if I open up a little bit and ask for some help.
So, what I am thinking about doing is using a 12V incandescent bulb to build a compressor/limiter type of module, with a gain pot to control the input gain and a volume pot to control the volume level after the bulb.
As far as my extremely limited knowledge goes, if the voltage going into the module’s audio input is 2-3V, I would need something to boost that voltage, correct? And then something to bring it back down afterwards? Or, would it be more prudent to go for a 6V bulb?
I am aware that there are easier and simpler ways to make this kind of module - that’s not the point, though! I want to see if I can get this to work.
(For the general case, you need a suitable bulb, an amp powerful to light it up, a load on the other side, and an attenuator to bring the output level down to a suitable signal level. Or you can just put the bulb between your amp and your speaker, like Sam does in that video.)
This video is actually what got me on this kick in the first place. So, if I built a simple VCA and had the output going into the bulb, and the other lead from the bulb connected to an output - would that work?
Doubtful, the light bulb has very low resistance and the VCA probably could not drive it. You’d need more power to light it up than a typical synth op amp could supply. A 10 watt 12 V bulb would draw 800 mA fully on and you’d be lucky to get a small fraction of that. A guitar amp is designed to drive a low resistance load (the speaker) which is why it makes more sense to put a bulb there.
