From 1981 Inventions:

"LVL is a professional low-gain device, which achieves overdrive gain ranges with a new and unique circuit. A combination of light clipping and op-amp push gives the pedal a unique sound and gain structure.

This is the pedal I have always wanted to make. To me, it’s a perfect low-gain stage. It’s the culmination of a 4 year process, and a collaborative effort with my friend John Snyder of ELECTRONIC AUDIO EXPERIMENTS.

It works great on bass, which is what FULL-RANGE refers to. It also stacks with anything, makes most fuzz better if you put it after, makes most overdrives better if you put it before. It’s also great if you hit the front end with a little boost!

I can play an entire set with my band - Relient K, using only this pedal. If you’re familiar with our recordings, LVL is the Forget And Not Slow Down sound, where as DRV is the sound of Mmhmm."