A version of the classic Rangemaster circuit.
The original 1960s units were amptop boxes with just a level control.
This version adds an input capacitor blend 'Tone' control, and added drop down resistors to help combat 'popping' when the circuit is switched in.
Great for brightening up and pushing a dark sounding valve amp.
Can also sound good after fuzz for tone shaping and before fuzz for boosting though the background noise levels raise a bit with the latter combination.
This one uses a proper OC72 black glass transistor which was used in the original rangemasters.