The Boost mode features a clean boost controlled by the pedals volume control, which will not affect your original tone. It can also be used for boosting the signal which can sometimes be lost when using long leads (particularly with single coil pick-ups). Blues mode is reminiscent of the tonal and distortion characteristics of our non Master Volume amps, such as the classic Bluesbreaker combo from the 1960s. This mode produces a wonderful natural style overdrive for crunchy chord work and singing single notes for truly inspirational leads, all delivered with the warmth and tonality of those early Marshalls.