In 1975 I bought a Systech Overdrive and I still have it! (see pics). It's a very unique overdrive (it's actually a distortion) since it has an "eq" control. The EQ control is a sweep of frequencies from 122Hz to 900Hz and sounds like a cocked wah. Rather than explain the what it does, Catalinbread wrote a blog about it HERE. and they describe it very well.
Since the sweep can remove A LOT of treble or low end depending on where you set it, I found that it would benefit from having active Treble and Bass controls (when they are set to 12 o'clock, it's flat, and sounds like the original pedal). It also has a relayed true bypass.
If your looking for a totally unique sounding distortion pedal, for use with a guitar or bass, this one is it. This sale is for the one pictured.
