D*A*M: Ezekiel 25:17 Low Frequency Distortion Generator, 0.15" Vero Layout

So I just worked out why I purchased some Motorola MC1748CG tin can op amps - it was to make one of these.  I've had them in my parts draw for a while, trying to remember what they were supposed to be for.  I thought maybe the Hudson Sidecar, but no, I need a dual for that.

Anyways, here it is, and I may refine this a little more at some stage or post something smaller on regular vero, as this is really for my own purposes - I doubt anyone else will want to make this at this size using these op-amps.   I almost did the full-size one on tagboard, but that was even bigger.

D*A*M EZEKIEL 25:17 LOW-FREQUENCY DISTORTION GENERATOR - VERO LAYOUT

EZEKIEL 25:17 VIDEO DEMO

GRETSCH: Play Boy Harmon Booster

OK, so this one is wide even by my standards - but it will still fit in a 150BB in landscape format.  I could have made it a bit smaller, but once you get past a certain width, why hold back is my theory.

The Gretsch Play Boy Harmon Booster was one of my early vero builds, using a layout by Mirosol on Guitar Effects Layouts (also known as the Jen Harmon Booster).   

It's pretty cool, and a little unusual at the same time - and it's not a booster by the way, it's a distortion.  It has quite a few buffer stages...   I tried a simplified version without the all the buffers, and it's just not the same.

It's open to some simple modding, as the tone section is a Big Muff style tone control.  The long tail pair amplifier arrangement also looks interesting.  

GRETSCH PLAY BOY HARMON BOOSTER - VERO LAYOUT

SCHEMATIC

VIDEO DEMO

FOXX: Tone Machine / Aion Vulcan, 0.15" Vero Layout

I quite like the Foxx, and for some reason today I felt like revisiting one, but this time going a little large.  

Layout below - not that anyone else is likely to want to build an oversized Tone Machine on 0.15" vero with 1w resistors (some standing), and leads popping out all over the place.  It's almost a demonstration of what not to do with a layout for some people.

I'm using the original glob top transistors, and a few tropical fish caps for some colour.   Pretty sure I can fit it in a 150BB enclosure (just).

This is using Aion mods - if you are unfamiliar with the Aion Vulcan, it's a Tone Machine with a modded EQ section (which is great) and an additional bypass option on one of the diodes - also a cool addition. 

From the Aion build docs - which are always excellent:

The Vulcan is faithful to the original, but with two added modifications. First, the octave switch (normally just “on” or “off” in the original) now has a 3rd setting allowing you to bypass the series diode in non-octave mode. See build notes for more details on this. 

 

The second modification is to the tone control. The tone control of the original is somewhat similar to the Big Muff, but many people find it’s difficult to get good sounds from the treble side of the rotation. By increasing the value of the treble-side tone capacitor, it improves the usability. A switch has been added to let you choose between two different capacitors in addition to the original.

FOXX TONE MACHINE / AION VULCAN - WORK IN PROGRESS

And here it is ready for the box.  I often use a cardboard wiring jig to work from before boxing.

FOXX TONE MACHINE / AION VULCAN - VERO LAYOUT

AION VULCAN - TONE MOD

Here's what the responses look like on LTspice (distortion mode), with the tone control set to 50%.  

Increasing the 15n cap to 47n flattens the scoop, and the 1n and 2.2n can also go up a size if you prefer a flatter mid-range (not shown in responses below)

This is with the additional 22k resistor

Without the additional 22k resistor

FOXX TONE MACHINE - LTSPICE

Stock Tone Machine, no mods as a reference

Output in red, plus the response on either side of the tone pot on the distortion setting.  Mellow is blue, and bride is green.

Same again on the octave setting

FOXX ON THE SCOPE

This is straight from the first boost stage

And the version below has a six way switch for tone, as I got a bit carried away (how unusual).

ZVEX: Woolly Mammoth

After having played around with some random mic preamps on the breadboard and in LTspice lately, I thought I might go back to basics with a fuzz face derivative - the Zvex Woolly Mammoth.  Brother to the Fuzzolo and Mastoron (they all share the same bones).

ZVEX WOOLLY MAMMOTH - VERO LAYOUT

VIDEO DEMO

VOX: Thomas Organ Vox Solid State Amplifier Limiter

A portion of this is based on the limiter circuit in some of the Thomas Organ Vox Beatle amps, which were solid-state amplifiers.  This was meant to protect the power amplifier section from overloading - R.G. Keen has explained it way better than I could here on Premier Guitar.

So far, I've only tested the single circuit on a breadboard - and it sounds OK.  Kind of like a fancy Electra Distortion with more range.     

SCHEMATIC

LT SPICE TRACE

It looks similar to this on my scope on the bench - I'll record it next time and post the results.    

TRACE 2

Same again, but now twice the fun - starting to look more interesting.