1590A · 1 knob
Zvex SHO - Crackle OkayVerified
Based on the Z.Vex SHO - Crackle Okay
From the post
The Zvex Super Hard On has become one of the sought after boost pedals today. Derived from the preamp section of a 60s recording console, the SHO uses negative feedback to control the gain (which is what gives it the crackle when adjusting the knob). It's capable of being a clean boost and adding some sparkle to your tone, or pushing your tube amp to break up and creating a great overdriven sound.
If you want to add a master volume control to it, remove the 47k resistor and use a 50k pot. Lug 3 to the Out pad, lug 2 becomes effect out, and lug 1 goes to ground.
Schematic
This is a board layout, a drawing of where each part goes, and the post may link the schematic it was drawn from. Open the layout at Effects Layouts (blog). No KiCad fragment has been drawn for this circuit yet.
Parts list 11 rows
Report a wrong parseGot parts in a drawer? See what you can build with them.
| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 4 | ||||
| ×1 | 82Ω | 82 | read from the layout by eye | |
| ×3 | 1M | 1M | read from the layout by eye | |
| ×1 | 5.1K | 5.1k | read from the layout by eye | |
| ×1 | 47K | 47k | read from the layout by eye | |
| Capacitors 3 | ||||
| ×1 | 100nF | 100n | read from the layout by eye | |
| ×1 | 47uF | 47u | electrolytic; read from the layout by eye | |
| ×1 | 10uF | 10u | electrolytic; read from the layout by eye | |
| Diodes 2 | ||||
| ×1 | 1N4001 | 1N4001 | read from the layout by eye | |
| D1 | 9.1V Zener | 9V1 | read from the layout by eye | |
| Transistors 1 | ||||
| Q1 | BS170 | BS170 | MOSFET; read from the layout by eye | |
| Potentiometers 1 | ||||
| Crackle | C5K | C5k | Potentiometer | printed 5K Rev log; read from the layout by eye |