Mad Professor Ruby Red Booster Boost PedalBJF design guitar booster treble booster pedal with master volumeMad Professor Ruby Red Booster (RRB) is a combination of two boosters and a switchable buffer. The two boosters are based on the much sought after BJF Little Red Trebler and Red Rooster Booster, connected in that order and with a master volume control. The RRB can be used as a treble booster, a clean boost or an overdrive unit or any combination of the above. Inside the pedal there is a