Technical notes: harmonics and noise
An overdrive pedal pushes the amp’s input: all the noise from the chain (cables, pickups, pedal) is amplified by every following stage. A Legendary Tones module creates its gain inside the amp, later in the circuit: the preamp can stay set low to preserve note definition, and noise is dramatically reduced, even at high gain.
Saturation stays 100% tube, with no clipping diodes: harmonic response is rich and progressive, and the tone cleans up as soon as you roll back your guitar’s volume.
Note: on Marshall 2203/2204 built between 1976 and early 1979, the V1 pin 7 wire is unshielded and may squeal at high gain. Marshall fixed this at the factory afterwards; a technician can perform this recommended update, with or without a mod.