Lovepedal Delux 60 Mosfet Boost

Hadn't done a boost pedal in a while and hadn't done a Lovepedal pedal in a while either, so I'm killing 2 birds with one stone. The Delux 60 uses a Mosfet gain stage set to give clean boost or to push a tube amp into break up. It's simple but effective. This'll fit into a 1590a pretty easily too.

Fulltone Fulldrive 2

I got a request for the Fulltone Bassdrive, and upon examining the schematic for it and the Fulldrive, there's only a few capacitor value changes between the two, which I'll detail below. All that to say, here's the Fulldrive 2 Mosfet. It's a Tube Screamer circuit with some interesting mods on it. Schematic is easily found on Google. Note that the Boost function of this circuit only works when the overdrive portion is already engaged. Pots can be board mounted and if the switch numbering is confusing consult the General Layout Notes tab for clarification.

For those of you who are interested in the bass version of this, use this layout to populate the Fulltone 2 board for the Bassdrive:

Keeley Psi Fuzz

Happy Fuzz Friday, everybody. The Psi Fuzz is an IC/germanium hybrid fuzz. It takes some inspiration from the IC Big Muff, but with Keeley's own distinct design touches. Schematic can be found here.

Fulltone OCD

I've been meaning to redo the OCD with proper board mounted pots, so here it is. It's a development on the Voodoo Labs Overdrive, with MOSFET clipping and a simple tone control. Fulltone has made a few versions of this with a few minor changes over the years. They're all mostly the same, but the biggest differences is in the pot values. Below is a partial bill of materials outlining the differences between the first 4 OCD versions, along with a couple value changes to mod the bass response.

Catalinbread SFT

Here's a really versatile overdrive from Catalinbread. The SFT is based on Ampeg amps from the 70s, using JFETs to simulate tubes (like many of Catalinbread's other overdrives). The Stones/Stoner switch allows you to go from verge of breakup tones to near fuzz tones with the flip of a switch. This can be run off 18 volts and this gives extra headroom, so it may not be a bad idea to include a charge pump in your build. This layout reflects the newest version of the SFT, and the schematic can be found here.

MojoHand FX Iron Bell/Skreddy P19

For Fuzz Friday, here's another Big Muff based circuit to add to the collection. The Iron Bell is a variation of the Skreddy P19, the schematic of which was graciously posted by Marc from Skreddy a few years back. It's not based on any one classic Muff, but is Marc's unique blend of custom values, and features a boosted mids tone stack, with a switch to increase the mids. Shortly thereafter, the Iron Bell came out with a few mods, the biggest of which is the replacement of the Mids switch with a potentiometer and a few value changes. The layout below reflects the MojoHand iteration of the circuit, but the P19 can be built on the same board (see below for component changes). It's laid out for board mounted pots and should fit in a 1590B.

To make the Skreddy P19, made the following changes:

• Replace the Colour pot with an SPST on/off switch
• Change Q2-4 to BC550
• Change the following components indicated on the layout:
  * 200Ω
  ** 10k
  • 47nF
  •• 2.7k
  ‡ 6.8nF

Rebote Delay - 1590A

For those of you who didn't want 1590A week to end last month, here's another mini layout for you. It's an early iteration of the Rebote Delay that features a simple JFET stage at the input, followed by the PT2399 delay stage. Simple, yet effective. Note: mind the 3 electrolytic caps on their sides in the middle of the board. Here's the schematic for reference.

CMAT Mods Butah

Here's a Blues Breaker variation from CMAT Mods. Seems to be a blend of the original and second versions of the Blues Breaker. Originals use a 1N4148 for polarity protection, but a 1N5817 would be better. It's laid out for board mounted pots and will fit in a 1590G if you're into those.

One-Knobber Project

I haven't made a detailed project in a while, so for Fuzz Friday here's the One-Knobber. It's based on the old Dr. Tony Balls stripboard layout that covered the ColorSound One-Knob, D*A*M Meathead and Dark Meathead, and a one-knob adaptation of the '66 Vox ToneBender, and I've added the Ritual fuzz by Black Arts Toneworks.

Project PDF

555 Relay Bypass

I know there are a bunch of you out there who like your 555 timers, so this one's for you guys. This relay bypass uses a 555 as a bistable flip-flop combined with a simple relay trigger designed by MicTester. His original design uses a latching footswitch, but with the addition of the 555, a momentary switch can be used for a soft touch bypass. MicTester says that the relay must be a Takimisawa AL5WN-K, but they are easily found on eBay and other vendors. Schematic and further discussion can be found here.

Keeley 4-Knob Compressor

The Keeley 4-Knob Compressor is a modified Ross Compressor and is highly regarded in the stompbox world. It's only down side is the use of the obsolete CA3080 chip. These can be hard to find and a little pricy. However if you're unable to find one, or unwilling to pay for one, use the LM13700 chip (which is 2 3080s in one) and this conversion daughter board. The schematic can be found here. If you have a hard time getting 150k pots, use a 250k pot with a 390k resistor in parallel (between lugs 1 and 3).

Galactic Fissure

I thought I'd close out Synth week with a fuzz designed specifically for synths. (Fuzz Friday waits for no man!) This one is pretty straight forward and I don't have much to say about it. Schematic can be found here. I added a pull down resistor to the input in case some one builds it for guitar, as well as polarity protection and power filtering.

Devil's Triangle Drone

Here's a synth circuit from Paul in the Lab (schematic and sound samples can be found over there). I've laid it out for board mounted pots with the board vertically in the enclosure. See the drilling template in the library for a visual. Here's what Paul had to say about it:

This is a project based largely on the put up or shut up mentality, for quite some time I've been getting annoyed at seeing youtube videos of people pissing about with these "synths" which are basically boxes of 555 timers with a million knobs that make stupid noises that you couldn't ever actually use in music so I thought I would make my own little synth that would get repeatable sounds and be useful in music and what better type of synth? a droner type - basically cause I love bagpipes - I like drones.

Anyway the circuit itself is quite a simple one basically because I only designed it during the week, all it is really is 3 triangle wave generators configured to operate in the audio range going into a mixer op-amp configuration with the odd filter here and there to soften the waveforms
I've used LM358 op-amps cause they are the cheapest, I'm not too sure if others would work in the same way though they probably will.

Why call it the devils triangle - well it has 3 oscillators one of which can oscillate a slightly high pitch range (for melody) it also sounds demonic so the name fit.

If you want to implement on/off switches for each oscillator, replace these jumpers with on/off switches.