through-hole

Through-hole describes components with leads that pass through holes in a circuit board and are soldered on the other side, as opposed to surface-mount parts¹. In pedal descriptions it signals hand-wired, mod-friendly construction, as in the DOD 250 50th Anniversary's socketed LM741 op-amp and through-hole components²³. Builders such as Stomp Under Foot and Shnobel Tone advertise hand-built pedals using through-hole components⁴⁵. Some circuits mix formats, like Electro-Harmonix reissues using through-hole capacitors, diodes, and transistors with surface-mount resistors⁶⁷. Through-hole versions of some parts, such as 2N5457 and J201 JFETs, are no longer available, prompting adapter boards or surface-mount substitutes⁸⁹¹⁰.