sound to light units.

ya, that's what it should do..... just like light rings made for subwoofers and stuff. generally when the sensitivity is adjusted correctly, unless there is a sound the lights stay off, they simply react to sound, or noise rather. with this one, there is currently no mic, so the lights should be off. they remain lit and go nuts when i turn the pot. I'll see if I can get a video of what mine is doing later, but no promises on that one. still no word on the velleman forums though.

If it got better when yoiu installed the capacitor, try connecting it to a different power source.  If it is a 12 volt device try connecting it to your car battery.  If 5 Volt, use your car battery and a 7805.Let's Go Brandon Brown. Congratulations on your first Xfinity Series Win. LGBFJB

ok, I connected it to a 9v battery, and it seemed to fix the problem, however the pot still does see ma little wonky or the unit itself is REALLY sensitive. even when connected to a battery, when adjusting the pot sometimes the lights will just go solid, and stop reacting to sound.... a little twisting of the knob and it will start working again. Adding the 1000uf cap with the battery does make it work a little better but it still acts weird or is overly sensitive.

A carbon potentiometer, or any pot for that matter, is a noisy device.  If it is hard to get the sensitivity where you want it, we may have to build a resistor network and change the value of the pot.  Set the pot as close as you can to where you want it to work, then remove the pot and read from the lone pin to each of the 2 side by side and let me know what you get.Let's Go Brandon Brown. Congratulations on your first Xfinity Series Win. LGBFJB

I think I killed the output transistor now. I shorted out one of the LEDs by mistake, and now it doesn't work. I'm going to have to see if I can get another BC557 transistor. I did order another one of these kits, but it probably won't be in for a couple of weeks. I'll harass velleman some more and confirm if I did kill the transistor, it shouldn't be hard to get another.