Introduction

If you like funk your going to love this effect. The main idea of an envelope follower is to create a voltage that describes the envelope of the signal being fed in. It is essentially an amplitude detector. If you could watch the input signal on an oscilloscope you would see that there are peaks and valleys in the amplitude signature. If you drew a line along the top of the signal you would be imagining what the envelope follower voltage looks like. Now we take this voltage and control a low pass filter with a nice amount of ring and put the original signal through that. The result is a great auto-wah sound with tons of character and responsiveness. Of course you can go out and buy an envelope follower at a music store, perhaps cheaper than the price of building this project. If all you want is the effect THAT is DEFINITELY the way to go. However, if you want to exercise or cultivate your electronic skills, get your soldering iron out, and feel the accomplishment of making your own very cool instrument effect then THIS is definitely the way to go.