Lighting a LED with a guitar signal

[rockgardenlove]

So somebody at another forum asked how to light up some LED's depending on how hard he played.  I've worked out a system pretty well, what I'm doing is sending the signal through an op-amp to boost it, and then the output goes into a bipolar transistor that controls current to the LED...

It's really finiky, and eats huge amounts of power, but it's about all I can think of really.  Any ideas?

[Marcos - Munky]

Use an envelope follower. It gives an voltage output based on the audio input and it's dynamics. You can just wire the voltage output to the LED.

[Leviathan]

Whoa, this sounds like a really cool project. If it works, let us all know!

[Leviathan]

Hey rockgardenlove, look what I just found... http://www.diystompboxes.com/smfforum/index.php?topic=37679.0

[Satch12879]

The Keeley Ultra Seeing Eye mod to the DS-1 does this.  You replace one of the clipping diodes with the actual check LED from that same box and there's enough going through it to light up as you play.  Very cool and very tasy mod.

[petemoore]

  I've seen distortion circuits light 'em up IIRC.
  Nurse Quacky has that LED light up / Env. Thing.

[comfortably_numb]

My Goldtone overdrive does this.  It's just got an LED clipper to ground.  You could put it on a long lead and push it through a hole in the box.  This is just like an OD 250 clipping circuit, but probably with higher gain, though it glows with low gain as well.

[KerryF]

hey That_Pink_Queen