This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Monday, August 29, 2016

Valve Wizard Equinox II

Here's a reverb circuit that doesn't require a Belton brick–the Equinox II by Valve Wizard. It uses 2, PT2399 delay chips with a pretty standard input/output buffer built around a TL072. The original uses a J112 for switching the tails function, but I've simplified that with a just DPDT footswitch. Use one side of the DPDT for turning the reverb on/off, and the other side for LED indication. If you don't want/need tails with your reverb, just jumper the 2 switch pads. It's gonna be a tight fit in a 1590B, but if you shave down the sides of the board a bit it should fit.

Friday, August 26, 2016

Catalinbread Merkin Fuzz

Here's an older one from Catalinbread, but a great sound fuzz for Fuzz Friday. It's based on the Mosrite FuzzRite but adds another gain stage after the Texture (Depth in the original FuzzRite) control. Schematic can be found here.

Wednesday, August 24, 2016

Menatone Red Snapper

Gotten a few requests for this one. It's a based on the Tube Screamer, but without the input and output buffers and a modified tone section. I've laid it out for board mounted pots and the electrolytic caps are folded on their sides.

Monday, August 22, 2016

Earthquaker Devices Grey Channel

This is the 400th layout on the blog. Kinda hard to believe I've drawn up that many. O_O

The cool dudes from Akron cooked up the Grey Channel, a dual overdrive based on the classic grey spec DOD 250. The 250/Distortion + circuit is one of my favorites and it turns out it's one of EQD's favorites as well:

It is based around a classic hard-clipping gray box overdrive (subtle hint, huh), one of my all-time favorites. Coincidentally, this is the very same pedal that got me started building pedals and launched EQD. It is two channels of a simple hard clipping overdrive that leaves the character of the guitar and amp intact. The Gray Channel retains the classic warm overdrive sound and expands upon it with several clipping options and bigger bass response. Each channel has 3 clipping modes. The Green channel- “Si” (Silicon clipping diodes), “Ge” (Germanium clipping diodes) and “N” (no clipping diodes). The “Si” mode will be bright/loud/fuzzy and has a natural tube type break up. “Ge” mode is a little looser with more lows and warmth and less output. “N” mode acts as a clean boost until you hit roughly 1 o’clock on the gain, at which point it’ll start to saturate the op amp into a biting, loud distortion. Phew! Still with me? Cool, onto the modes of the Red channel. Here, you’ve got “LED” (LED clipping diodes), “FET” (Mosfet clipping diodes) and “N” (again, no clipping diodes). “LED” mode is the loudest, cleanest and most touch sensitive/least compressed. “Mos” mode is the most compressed with a tighter crunch; the biggest hesher of the group. And finally, the “N” mode is the same clean to crazy loud op amp distortion set-up as the Green channel. With a couple of switch clicks you can go from your bypassed tone to warm break up to over-the-top gnarly grind and any/every combination in between.

Using the above info from the EQD product description, I've come up with a work-a-like to the Grey Channel. Using the Grey Spec 250 schematic as a base, I drew up 2 of them using a single 1458 IC (a dual version of the 741), increasing the value of the input capacitor to 22n (feel free to adjust that to taste) for extra bass response and including the various clipping options outlined above. I also changed the value of the gain pots from C500k to B1M, which is a fairly common mod to 250/Disto + circuit.

You can wire two separate on/off footswitches if you want, but if you want to wire it like the original with a master on/off and then channel selection, wire it like this:

Connect X to X and Y to Y. If you want to use a bi-color LED in place of D2-3 you'll need to wire it like this.

Friday, August 19, 2016

Wampler Velvet Fuzz

The Velvet Fuzz is a unique fuzz that combines amp emulation and 2 different selectable fuzz tones. The toggle selects between a LM386 (Tight) circuit, and a 2N5089 (Big) circuit. These then push a Plexi Drive circuit that gives the Marshall amp emulation. The modular nature of this design gives you the option to have not only a Velvet Fuzz, but a Plexi Drive in the same box. The board is laid out for board mounted pots and I've included trimmers to help bias the J201 JFETs. I've also included a switch diagram to show how to wire the toggle switches.

Wednesday, August 17, 2016

Wampler Cranked AC

Another amp emulation overdrive from Wampler that's supposed to sound like (you guessed it) a cranked Vox. This one has been discontinued, but was very popular. It's very similar to the Plexi-Drive, but doubles the transistors and there are a few component changes. I've added trimmers to help bias the J201s.

Monday, August 15, 2016

Wampler Plexi Drive

I'll give you heads up now. This is going to be Wampler Week. I laid out the Plexi-Drive a long while ago, but I wanted to give this "Marshall-in-a-box" circuit another go with board mounted pots and trimmers for those pesky J201 JFETs.