Named for Stevie Ray Vaughan (Lenny is, of course, an instrumental track dedicated to his wife), this simple two-knob boost and tone conditioner has roots in the sound of a Dumble Steel String Singer amp, as used by SRV, being pushed hard.
Designed to colour your tone with a midrange character reminiscent of that amp, it will give your guitar real presence in a mix. The Tone knob's range works perfectly with your amp to focus the top-end where you need it and is capable of bringing out a plangent chime.
Even without too much in the way of boost, this pedal is a lovely tone improver that feels good to play through, but if you do want to drive your amp harder, there's plenty here to get it sweetly singing. Our favourite use, though, is in front of an overdrive pedal where it proves a superb tool to really squeeze out the juice, kicking things to the next level.