The Joyo Ultimate Drive is based on the Fullt*ne OCD pedal. Gives you that rich heavy, bordering-on-distortion overdrive, surpassing what a diode tube amp can provide. Open it up and find the kind of saturation and spacious harmonics of a big overdriven tube amp. Very powerful drive possibilities for that thick crunching sound for riffs and leads. Gobs of gain, and then even more gain which is why it’s called the Ultimate Drive.