Can you help me understand how the two highlighted sections affect the first stage? I understand the first part is the range control; is the lower part of that first section adjusting the upper cutoff frequency of a low-pass filter? What is the path through the lonely 4n7 cap doing?
For the second portion (in the orange box), is this just a HF filter for the emitter side of the transistor? Maybe you can point me to a resource that would help me understand the sections of each of the gain stages in this pedal more clearly?