SONIC VI: Silicon MKI Tone Bender

The SonicVI silicon MKI Tone Bender is firmly based on the original, with a few additions and some minor changes.  

Being silicon based, the transistors do not self-bias, so additional resistors have been added from V- to the base of Q1 & Q3. 

The transistors used are early Mullard PNP silicon OC202 which are quite low-gain and still available at reasonable prices.  In terms of gain, it's down in the 40-120hfe range.  

I tested some random vintage silicon transistors that I had handy, and around 85hfe did the job.  Being silicon, this is easily flipped to NPN by reversing the electrolytic caps, as long as you have similar transistors.  I've tested with PN2222A and it was fine.  Out of the transistors tested, the lower gain vintage ones sounded a tad better to my ears - I suspect this has more to do with hfe than age. 

ASSUMPTIONS

Given I did the layout based on a photo from Reverb, there are some unknowns - not too many though, as most of the values are clearly visible.  

Trimmer:  A 25k to 50k trimmer works well, set on the edge of gating to get that MKI decay.   

Attack:  The Attack pot is paired with a 150k resistor - 50k is fine, quite possibly with a low value resistor hidden under the board.  Tune it so it just cuts off with the pot on zero.  I'd say test this with a couple of different size pots (50k or smaller), to see what suits you.

Level:  I've assumed the value of the Level pot to is 500k, which is the same as a MKI

SONIC VI SILICON MKI TONE BENDER - EYELET BOARD LAYOUT

I added the 100uf that's seen off-board in the photo to the layout, as it's just a bit easier to attach here, vs the DC jack.

photo care of Reverb listing

MULLARD OC202 DATASHEET

SONIC VI SILICON MKI vs PIGDOG MKI

STANDARD VERO VERSION - NPN

I guess not many people will be interested in the eyelet version, as cool as it may look - and this is NPN that will fit in a 1590B enclosure.

version 1a - error corrected on v1.

BREADBOARD TESTING - WORK IN PROGRESS

It’s sounding really nice on the breadboard.  Sharp attack, same frequency response as a stock MKI, and there’s even the spitty decay on the end of notes.

It did pickup radio on the breadboard and squelch a bit - a low value cap on the input sorts this out.  Not sure what I even have on there at the moment as I picked up a random small greenie off the bench - think it's 3n3.  Needs a cap on the power supply, again, helps with noise.    

Tested with;

2N4036 PNP Silicon (vintage ones, although they were in production until quite recently)

Q1   86hfe    Q2   81hfe      Q3 106hfe 

PN2222A NPN Silicon (new)

Q1 - Q3, approx 220hfe

CARLSBRO: Fuzz-Tone

This is a rather interesting looking fuzz - one that I had overlooked until someone pointed it out to me (thank you Mister Hate).   Before this, I was only aware of the MKIII-style fuzz that Sola Sound made for Carlsbro.  

Despite having three transistors and being made in the mid-sixties in the UK, it is in no way related to a Tone Bender / the Maestro Fuzz-tone.

   

History:  Link to Fuzzboxes (excellent site by the way)

Discussion: Link to FSB

CARLSBRO FUZZ-TONE   |   POINT-TO-POINT LAYOUT

So this is based on the original, with a few minor changes regarding placement.   The layout on Freestompboxes did get me started, so credit to all those involved.

The original board is quite a mess (check the photos on fuzzboxes.org), which is why the transistors aren't shown.  The transistors sit above the resistors and capacitors on the board.   

ORIGINAL SCHEMATIC FOR THE FUZZ-TONE

I redrew it, as the original was making my brain hurt.

This kicks out a pretty mean-looking wave - I’ll attach some actual scope traces a bit later.   

It looks like it has a focussed mid-range

MODS FROM THE BREADBOARD

Jumper / remove the 100k resistor on the input

Remove 220k on output 

Move attack pot 2 to V- 

Increase input and output caps

The Selmer Buzz Tone - three volts of nasty sixties guitar fuzz.

I'd strongly recommend reading this first before committing to a build.  If you don't, disappointment will most likely follow.  Most mid-sixties three transistors fuzzes are notoriously fussy about transistors / biasing.   

Plenty of discussion in all of the usual places regarding what works and what doesn't.  

SELMER BUZZ TONE    |   POINT-TO-POINT LAYOUT

ORIGINAL BUZZ TONE SCHEMATIC

VIDEO DEMO

PETE CORNISH: TB-83 Treble Booster, Point to Point Layout

I followed a vaguely similar layout to the one pictured at the bottom of the post for the Pete Cornish TB-83 Treble Booster.   

This is a straight treble boost using a silicon transistor - it's going to sound horrible into anything apart from a cranked valve amp, or maybe a valve based pedal.  Given this was in Brian May's rig, think normal channel of a cranked AC30, with this hitting it.  Well maybe you aren't running nine AC30s at once, all running so hard the border on catching fire, but you get the idea.

PETE CORNISH TB-83   POINT TO POINT LAYOUT

PETE CORNISH TB-83 - LTSPICE

I used the schematic from Fryer Guitars - link here.  

Another Lovepedal, another Electra Distortion with big marketing claims...    

I found this one in my folders from a while back, so I thought I may as well do a quick update and post it incase someone is looking for an easy point to point effect build.

LOVEPEDAL ENGLISHMAN - POINT TO POINT LAYOUT

Here's a nice easy one if you haven't done anything point to point before - the Zvex Super Hardon.  

ZVEX SUPER HARDON - POINT TO POINT LAYOUT

I've left some room on the board for added power filtering / protection.

I haven't done a point to point layout for a while, and I also remembered that I've been meaning to make a Zvex Fuzz Factory for some time, but have never quite gotten around to it.  So here it is.   

I tried a Fuzz Factory using a different layout as one of my first guitar effects builds on vero, and it didn't work well at all - so much so that it ended up in the bin.  Maybe better luck this time with a bit more experience, and I have a couple of AC128s that could do with a home.  Think I tried some dodgy AC125s for the build that didn't work well, it was some time ago, so who knows what I did.

ZVEX FUZZ FACTORY - POINT TO POINT LAYOUT

I would recommend breadboarding this prior to committing to solder.  The Interfax Harmonic Percolator is very tweakable, and sometimes takes some adjusting to get it right.  

There's pages on the Harmonic Percolator on DIY Stompboxes.

INTERFAX HARMONIC PERCOLATOR - POINT TO POINT LAYOUT

JORDAN: Boss Tone, Versions 1, 2 & 3, Point to Point Layouts

A nice simple one - the Jordan Boss Tone.

JORDAN BOSS TONE V1 - POINT TO POINT LAYOUT 

The California version.

JORDAN BOSS TONE V2 - POINT TO POINT LAYOUT 

Still the California version, with a few minor variations.

JORDAN BOSS TONE V3 - POINT TO POINT LAYOUT 

This is the NPN / PNP transistor version, also known as the Nashville version.

MSA PEDAL STEEL FUZZ - JORDAN BOSS TONE V3 - POINT TO POINT LAYOUT 

This is a minor variation on the V3, Nashville Boss Tone.  This circuit was built into some MSA pedal steels.

Note:  The 100 ohm / 47uf cap power filter is not present on the original, as they were all battery powered (and there was no room in the tiny enclosure for unnecessary extras).

This is one of the first circuits I ever built due to the simplicity, and it's hard to go past as a simple boost with a bit of fattening up of the signal.  

The Echoplex EP-3 preamp doesn't provide tons of gain, but it does work very nicely as a slight boost, or as an always on type effect.   I plan on adapting this to be the front section of a Valve Caster, to provide some extra grit. 

I used the Aion Electronics schematic, as I like the idea of the fat switch, but I did not include the volume control or output buffer.  Pretty easy to add a volume control, I'm sure anyone reading this knows how.  

ECHOPLEX EP-3 PREAMP - POINT TO POINT LAYOUT

version update:  corrected switch wiring.  pin 2 to ground (thanks Solderholic)

The Hudson Electronics Broadcast is a great little pedal - while now overshadowed by the Dual Broadcast, which has the high and low gain settings on a foot switch with individual level controls, it's essentially the same under the hood.  

I never thought a lo-cut pot would be so useful until trying this pedal.  It has a decent range to it, from clean through to near fuzz.  It can get quite nasty too with the lo-cut.

This runs at 24v, so you will need to build a seperate charge pump, unless you have 18v or 24v outlets on your pedal power supply (which is what I do).   Otherwise you can always run it at 9v.  It works, it's just not as dynamic - and maybe sounds a little flat by comparison to running at 24v.

HUDSON ELECTRONICS BROADCAST - POINT TO POINT LAYOUT

Note:  If you use a different isolation transformer, you may need to make adjustments to the 15k / 33k resistors before the transformer.  The resistors and one half of the transformer form a RL high pass filter - I had this issue and could not for the life of me work out what was happening until someone more experienced than I pointed this out.  I couldn't work out why I had a full range signal coming from Q2 and the coupling cap, but it disappeared at the transformer. 

HUDSON ELECTRONICS BROADCAST - CIRCUITLAB SIMULATION

Follow the link to Circuit Lab to play with a simulation of the Broadcast - at least until they lock you out and ask for a subscription.  

https://www.circuitlab.com/circuit/43q3t2mjg3ev/hudson-electronics-broadcast/

One of the pedals that put Death by Audio on the map - the Supersonic Fuzz Gun.  It has been reported as quite hit and miss depending on the exact type of transistors used, so best to breadboard or prepare for some experimentation.

2 x MPSA06G and 1 x BC517 (Q3) are reportedly a better choice for transistors.  As always, check pinouts.

DEATH BY AUDIO SUPERSONIC FUZZ GUN   |    POINT-TO-POINT LAYOUT

The Ghost Effects Lunar Incantation is part Mosrite Fuzzrite and part Rosac Nu-Fuzz - what a combination...   time to break out some NOS low-gain silicon transistors? Maybe not.  BC108s will be fine; probably anything with lowish gain that's NPN silicon will do.  Ghost Effects recommend 150 to 300hfe, with the second transistor having a higher gain.

I've left enough room for power filtering/diodes / 1M input resistor etc, if you want to add that.

GHOST EFFECTS LUNAR INCANTATION - POINT-TO-POINT LAYOUT

GUILD: Foxey Lady, Point to Point and Vero Layouts (two knob version)

This is an early two knob Guild Foxey Lady, which is very similar to a silicon Mosrite Fuzzrite.  However it’s different to other schematics I have seen online -  

I traced this from the circuit shown below - it's easy to make out part values, excluding the pots and transistors.  I left some room for power filtering too, should be able to fit an extra cap / resistor / diode on there without any trouble.

GUILD FOXEY LADY - POINT TO POINT LAYOUT

GUILD FOXEY LADY - VERO LAYOUT

As you can see I converted the P2P layout to vero - could have been smaller, but no matter - it's still on small side of things anyway.

GUILD FOXEY LADY SCHEMATIC

I traced the circuit from the photos below, taken from David Morrin's website (hope you don't mind me using them Dave).  

 I don't know what the actual pot values are - the usual suspects for a Guild Foxey Lady would be a good starting point (100k).  Dave mentions that they are dated 1968.  Not sure about the transistors either, 2N5133 or similar is a distinct possibility. 

The traced circuit is a lot brighter than the standard schematic - no surprise given the 1n cap on Q2 instead of the 3n3

SPACEMAN EFFECTS: Atlas III Preamp Booster, Point to Point Layout

I had a few of the FETS leftover from the Spaceman Saturn V Harmonic Booster, and I saw the layout over at Perf and PCB Effects Layouts, so I thought I might try one of these.  

The Spaceman Effects Atlas III is another booster, following the theme of rocket engines in naming (nice).

The switch is a phase switch, it literally just inverts the output phase.  So perhaps mount this on the side, or somewhere out of the road, as you won't be making use of this very often, if ever.   It could easily be completely removed, and I'm sure you can work out how to do that yourself.

SPACEMAN EFFECTS ATLAS III BOOSTER - POINT TO POINT LAYOUT

And on the eighth day...  well not exactly that long ago, but close - and yes others came before, but it's hard to not acknowledge the Arbiter Fuzz Face as being a giant of vintage fuzz, a design icon if you like, with possibly the most widely recognised enclosure ever made.  It's hard not to like a Fuzz Face.  

ARBITER FUZZ FACE - POINT TO POINT LAYOUT

GHOST EFFECTS: Warmjet V

This is the Ghost Effects take on the WEM Project V - the Warmjet V.  The name is a combination of the original WEM Project V, and the Brian Eno album, Here Comes the Warm Jets, which the pedal was allegedly used on and supposedly remains a favourite of Brian Eno (according to the internet, so it must be true).

It's basically a WEM Project V, with a few parts removed, which are arguably unnecessary.  The overly complicated tone/gain switches have been replaced with an Edge pot - probably not a bad idea.  

The vero below is a trace from the pcb and build documents published by Ghost Effects - who kindly also includes a list of potential mods in the build document.   Some models place all trimpots externally, which is a good idea if you have the space.  

GHOST EFFECTS WARMJET V - VERO LAYOUT

GHOST EFFECTS WARMJET V - POINT-TO-POINT LAYOUT

This is not an easy build - if you are not confident with point-to-point, stick with the vero layout.  So many transistors...   

I changed my mind and made the 50k trimmer an external pot.  I also moved some leads around to make it neater.  The layout is the same; I tucked leads under the board and resurfaced them elsewhere.  

CHANGES FROM THE WEM PROJECT V

First, load up the schematic.  

These parts have been removed

• 47n on the power supply/power filtering 
• The inductor between Q1 & Q2, which no one seems to know the value of anyway 
• 22pf, 390pf and the 100k resistor from base of Q7 to ground
• 50uf cap from collector of Q1 to ground
• the entire Edge / Drive switching system (replaced by Edge pot, which is a trimmed-down version of the filter system)

FREQUENCY RESPONSE OF EDGE CONTROL

The main difference between this and the switches on the Project V, is basically you get a good scoop with this one, and maybe a bit more bass is retained.

There are a lot of mods mentioned in the build doc linked above, so maybe have a read-through.  examples:

If you want to let a bit more square wave through, drop the 100k resistor going to Edge 3 to 10k - OR increase the volume pot to 5k.

Removing 10n in the filter section and replacing it with a jumper changes the Edge pot to a high-pass filter.  

SCHEMATIC

UNIVOX: UD-50 Unidrive, Point to Point Layout

Univox Unidrive boost with Aion FX mods

The original Univox Unidrive was a straight boost, with a bit of dirt - it was a large rocker pedal with preset gain levels on a rotary switch, and the rocker controlled the output level, not unlike a regular volume pedal, but with the increased level of a booster.  The don't really make guitar effects like this anymore, and perhaps for good reason when consider the practicalities.

The Monad adds a capacitor blend on the input to swing form top boost through to full range, and adds a pot instead of a rotary switch for gain control.  There's also a trimmer added to control feedback between gain stages - might be worth trying a larger value, or even changing this to an external pot.

UNIVOX UNIDRIVE - POINT TO POINT LAYOUT

UNIVOX UNIDRIVE SCHEMATIC

If you would prefer to make the stock model, I'm sure you can make adjustments to suit using the schematic.