Originals and parts

Originals

Originals lists the commercial pedals the circuits are based on, by brand and then pedal, with:

• Circuits: how many boards, layouts and schematics copy or adapt it,
• Built on: how many of those are PCBs and how many are vero, tagboard or other layouts, each count a link to just those,
• Sources and Category.

Type in Filter to find a pedal (klon, tube screamer), then pick it to open every circuit based on it in the Circuits table. From there the usual filters apply: only the ones in a 1590B, only the ones in stock, only the vero layouts. Every Big Muff Pi is a good place to see how far the boards of one pedal differ.

Different sources spell the same pedal differently (“Pro Co RAT Distortion”, “ProCo RAT”). Akashic files the spellings under one name, but a pedal and its later versions, such as the TS808 and the TS9 Tube Screamers, stay apart.

The parts cross-reference

Parts lists every part named by number across all the parts lists, grouped by kind: diodes, pots (by taper, then value), ICs, transistors, switches, trimmers, optocouplers, inductors, transformers and crystals. The number beside each is how many circuits use it. Resistors and capacitors are left out, since every circuit has them. Filter matches the part number and its description, so delay finds the delay chips and jfet the JFETs.

A part's page

Open a part, such as the LM308, and you get:

• What it is and how the parts lists describe it.
• The datasheet, linked from the maker's own site. For a discontinued part whose maker no longer publishes one, Akashic keeps an archived copy, and a part made by several fabs lists each maker's sheet. A part that is made again under a new number links the new part's sheet first.
• Every circuit that uses it, in the same table as the Circuits page.

Transistor substitutes

A transistor's page, such as the 2N5088, suggests substitutes from a database of transistor limits. Candidates share the material (silicon or germanium) and the polarity or channel, and are ranked by how close their gain, voltage, current, power and speed are. They come in two lists: parts that other boards in the library already use, and the closest by the numbers.

The database has no pinouts or packages. Before you drop a substitute in, check its datasheet: a different pin order means turning it on the board, and a different gain changes the sound, which is the point in a fuzz and a problem in a buffer.

IC, diode and opto substitutes

An IC's page, such as the TL072 or the LM308, lists the parts that fit the same socket: the same function, pin count and pinout. A diode's page, such as the 1N34A, lists diodes of the same kind, and a Vactrol's lists the other Vactrols. The figures are read off each part's datasheet, and the last column says what differs: a JFET or CMOS input, a supply limit below 18 V, a compensation capacitor the original did not need, a higher forward drop. Only parts with a datasheet in hand are compared.

Zeners

A parts list that gives only a zener's voltage, such as 9V1, gets a page listing the zener parts of that voltage, their power rating and package, with a note on which size fits a pedal board.

From a parts list to a part

On any circuit page, the Normalized column of the parts list links each numbered part to its page, so you can go from a board you like to every other board that uses its chip. From a part's page, What can I build on the Workbench takes the next step: which circuits the parts you have would finish.