ETI: The Fuzztone, a Dan Coggins Design

The Fuzztone is an early design of Dan Coggins before Lovetone or Dinosaural appeared.  

The first publication in ETI (Electronics Today International magazine) actually had an error on the schematic - it wasn't critical, as it just changed the frequency response a little, and it lost some level along the way in the filter section.  Remember that ETI supplied a PCB for the project, so it would have sounded right.  

You can find the corrected schematic and a few words from Dan here.

ETI, DAN COGGINS THE FUZZTONE - VERO LAYOUT

FUZZTONE ON LTSPICE

I've not built this yet, but it looks like a distortion/overdrive with a mid-hump and not much top-end on LTspice.

This is sweeping both the sustain and filter pots from 0 to 50% to 100%

THORPY FX: Heavy Water

A nice booster from Thorpy, most likely Dan Coggins design.  The build notes from PedalPCB suggest germanium diodes across the opamp for a dirty boost.

Schematic can be found here

THORPY HEAVY WATER BOOSTER - VERO LAYOUT

This puts out a lot of level, and the low cut can put it in treble boost territory on extreme settings without any trouble at all, otherwise generally handy to cut a bit of bass to tighten things up on the lower end. 

I haven’t included a trace of the wave, as it basically looks like a big sine wave - a bit of change with the bass cut, but nothing worth looking at.  

THORPY HEAVY WATER BOOSTER - VIDEO DEMO

DINOSAURAL: OCT-201 Opticompressor

Another day, another compressor layout...  This is a Dan Coggins design, the Dinosaural OCT-201 Opticompressor, and the predecessor to the Thorpy Fat General, which was also designed by Dan.

Not many of these are around, as it was only made in a short run.

Schematic and tracing journal on Aion FX.

DINOSAURAL OCT-201 OPTICOMPRESSOR - VERO LAYOUT

THORPY FX: Fat General Optical Compressor

While on a run of compressors, I thought this one looked interesting.  ThorpyFX Fat General is an optical compressor with a treble control and a blend function.

Schematic can be found on PedalPcb here.

It's said to be a progression of the Dan Coggins designed Lovetone OCT-201 - based on the trace at Aion FX, 

THORPY FX FAT GENERAL - VERO LAYOUT

The layout works - I have tested it using standard true bypass, but please read the comments below.  Seems to be some switching issues.  

 I used some proper vactrols that I forgot that I had in a draw and subbed a couple of resistor values as I was short a few.   

Sounds fine, although after playing with a few compressor/limiters recently, I think I prefer diode compressors.  The tone control is subtle and only obvious on certain pickup/compressor settings.  Still quite useful.  The blend is a cool feature, but not one that I tend to use on guitar. 

THORPY FX FAT GENERAL - VIDEO DEMO

DINOSAURAL: OPA-101 Overdrive Preamp

The Dinosaural OPA-101 Overdirven preamp is a variation (or improvement) on the Dinosaural Tube Bender.  

This is has the tone control like the the Aion FX version, but I did leave the output stage as a buffer as per the original.  The filter itself is on the original which you can see on the schematic / tracing journal.  Well worth a read as there's a lot of really useful background information on this pedal.

There's also the option to run this true, or buffered bypass.  Personally I'd run buffered, but that's just me.  

DINOSAURAL OPA-101 OVERDRIVEN PREAMP - VERO LAYOUT

LOVETONE: Big Cheese

While I'm doing Lovetone, I have to do a Big Cheese...  this is now the predecessor to the Thorpy Field Marshal Fuzz, now that Dan Coggins is helping out on the design side of things there.  

The schematic can be found at Aion Fx, and this version includes a bit of extra boost at the end.  I'd suggest reading the build docs (schematic) from Aion, as it explains how to set the trimmer and a few other things of interest.

LOVETONE BIG CHEESE - VERO LAYOUT

VIDEO DEMO

LOVETONE: Brown Sauce

Lovetone effects pedals are pretty legendary, and I have meaning to get around to some layouts for a while now.  I thought I might start with the Brown Sauce, which is the least challenging.  

You can find the schematic here on Aion FX - also check out the rest of the Lovetone line that they've traced too, as you will probably never want to attempt something like a Doppelganger on vero.   

LOVETONE BROWN SAUCE - VERO LAYOUT

BROWN SAUCE VIDEO DEMO

DINOSAURAL: Tube Bender

The Dinosaural Tube Bender from Dan Coggins of Lovetone fame, who now designs for Thorpy FX.  The Thorpy Fat General compressor is actually a Dinosaural OTC-201 Opticompressor.  You can read up on that here.

This is the most recent trace from Aion Electronics.   Aion do a pretty good job of tracing to say the least, so I expect it to be accurate.   

This is different to the magazine version schematic, which has the same topology but with some different values.  I built one based on the magazine version a while back, and binned it pretty quickly - couldn't work out what the fuss was about, as it was rather disappointing.  

I've built and tested this version, and it's nice little overdrive.  Runs from very clean, right through to a heavy drive, with a some very usable tones along the way.

The Aion Electronics includes a tone switch mod for more variety, and a bit more power filtering and protection.  I'd recommend building the Aion version, as you get more flexibility for limited additional cost and effort.

  

DINOSAURAL TUBE BENDER - VERO LAYOUT

AION ELECTRONICS WYVERN - VERO LAYOUT

note cut under 100 ohm resistor

BUILD PROGRES PIC

This is prior to adding power caps, diode and pots etc - just added enough parts to get it working on the scope.  

I used 2N5088 transistors, which are flipped compared to the layout for BC549's   LIke any build, always check your transistor pinouts.  Always...   

DINOSAURAL TUBE BENDER ON THE SCOPE

Input signal:  440hz sine wave, approx 130mv TRMS

Gain 0% Q4

Gain 50% Q4

Gain 100% Q4

Gain 100% Q4, 3n3 capacitor (Tone 3), Tone switch off

Gain 100% Q4, 10n capacitor (Tone 1), Tone switch off