The individual parts on any circuit's bill of materials — pedal, guitar, or amp — and what each one actually does.
Resistors restrict current flow and set voltage levels; capacitors store charge temporarily and block DC while passing AC. Together they set every bias point, tone control, and filter cutoff on this site, whether that's a pedal's clipping stage, a guitar's tone knob, or an amp's power supply — this chapter covers how each behaves, how to read their markings, and which types matter.
A transistor is a small current controlling a larger current — the basis of amplification and, when overdriven, distortion. A diode only lets current flow one direction — the basis of clipping. This chapter covers both, including why germanium vs. silicon and symmetric vs. asymmetric clipping define the character of fuzz and overdrive circuits.
An op-amp is a general-purpose amplifier that compares two input voltages and outputs a hugely amplified version of the difference, with feedback resistors setting the actual gain. This chapter covers how op-amps behave, why the inverting configuration dominates pedal circuits, and why chips like the TL072 and 4558 show up constantly in overdrive designs.
A potentiometer is a resistor with a movable tap, turning a fixed resistance into an adjustable one — it's the component behind every knob on a pedal, a guitar, and an amp alike. This chapter covers linear vs. audio (logarithmic) taper, the three-lug wiring convention, and why the wrong taper is the most common reason a control feels bunched up.