The Four-Speed Overdrive is an extremely transparent, dynamically responsive overdrive pedal. It has a gain control that sweeps across the range from boost to full on distortion and all levels of gain in between and a tone control that acts more like a presence control. Then combine this with the "Torque" Switch, a four-position switch that selects between four overdrive "colors" or "characteristics" and a "Rumble Boost" push-pull switch that adds more bottom to your signal you've got one VERY versatile overdrive pedal.
When the first Four-Speed Overdrive was built, I didn't realize the possibilities of a pedal like this. It was created to be the most versatile overdrive pedal for the guitarist who may be using more than one amp. Now, after all the feedback I've received I've found that it's most often used in three major applications:
First, for the touring musician that is often flying out for a weekend or overnight show and is using a scaled down rig such as one or two guitars, a pedalboard and a backline rental amp. The Four-Speed was designed to sound great with any amp so you need not worry about what type of an amp you'll bage when you step on stage.
Second, For the session guitarist who may need to pull more than one sound out of the same amp. You can cut rhythm tracks with a fat semi-overdriven sound then, with a few clicks and turns, burn out your lead lines with a rich and inspiring overdrive full of harmonics and sustain.
Third, For the musician who has an arsenal of guitars and amps to choose from. This allows them to use the same pedalboard and effects pedals with multiple amps. The type of pedal most switched out of a pedalboard is the overdrive/distortion pedal mainly because it is most effected by the amps characteristics. Here's the pedal that sounds great with any amp, tube or solid state!