Relay Bypass: conception and relay bypass code

You might already have heard about "relay bypass", or even used it without knowing it. It a different true-bypass system than the classical 3PDT switch. Instead of using a mechanical 3PDT switch, a soft switch, a microcontroller and a relay are combined to turn the effect on and off.

 So... Why bother? My 3PDT switch is great, don't you think?

As you may already know, 3PDT switches are the main cause of guitar pedal failure. These switches are not particulary though, and they often break, especially as we smash it continuously with our feet on stage.

A classical high quality 3PDT switch is rated for 30,000 activation cycles. With relay bypass, we use a relay that will play the mechanical role of connecting ins and outs. Relays are usually rated between 10 and 100 millions cycles! Thus, this system is much more reliable.

Moreover, the soft switch that we use to activate the guitar pedals also last longer than a 3PDT, usually around 50,000 cycles! They are also easier to replace, as there are only 2 connections to make with the relay bypass system, and not the full 3PDT wiring.

This blog post will present you how does it work, and how to make your own relay bypass system using a microcontroller, from the beginning to the end! Long stuff (but good stuff?)!

Guitar effects and reliability: 5 things to improve to make your pedals longer lasting

I am building effects since three years, and now that it has been a while, I noticed first failures on my devices. In this article I am going to describe what are the main causes of guitar effects failures that I noticed or that people report to me, how to repair it, and how to build your pedal to make them long term lasting or easily repairable.

1. 3PDT switches

3PDT switches are the main reason why a pedal stops working. A broken 3PDT switch can cut your sound, and the pedal is not easy to switch on and off. 3PDT (and switches in general) are mechanical devices that suffer when activated a lot of times. Usually, good quality switches are rated for 30 000 cycles, but with the way we treat our pedal (kicking them all the time on stage), they usually fail sooner than that. Moreover, most of the times, we do not use good quality switches, but rather “China Blue” 3PDT that are not that reliable (but way much cheaper than Alpha switches).

Replacing a switch is easy but sometimes quite annoying, as you have to rewire everything. To make replacement easier, you can use 3PDT miniboards and ribbon cables. This system is used in many commercial pedals, like in Electro Harmonix or even Diamond pedals:

But what if you just want something more reliable? Another solution is to use relays instead of 3PDT as a mechanical system to switch the signal. A normally open momentary soft switch can be used with a microcontroller to drive a relay to switch the signal. Indeed, relays are rated for way more cycles than mechanical 3PDT. For instance a Panasonic TQ2-L 5V, which is a classical relay is rated to last between 10 and 100 million cycles! The momentary switch is really easier to replace than the 3PDT switch, only 2 cables to solder. Here is an example from the Dr Scientist Bitquest pedal (great brand!):

 

I am planning on using this kind of system on my pedals soon. I have written a code for a PIC 12F675 microcontroller to use this kind of system. I am now designing a PCB to use it as a standard activation system, with some tricks. Also, this switching scheme is totally silent, which is nice!

2. Wiring dessoldering

When wiring the pedal, cables are not always really fixed, and the solder can break and cause a disconnection in your wiring. This can happen quite easily on the 3PDT jack where there is a lot of wiring going on, or even on input jacks. It can make the pedal mute, or generate a huge amount of noise if there are grounding issues arising from a dessoldered wire. It is easy to fix (just ressolder the wire), but quite annoying if the person cannot fix it at home (no soldering iron…etc) and needs to send the pedal over. There are two ways to prevent that. The cheap way to do it is to apply a kind of glue on the soldered wires to avoid physical stresses that cause unsoldering. This is the case in this Caline pedal (Chinese cheap clones):

But the best way to prevent it is to include the wiring directly on the PCB, ie include the jacks and 3PDT on the PCB. It is possible to use a separate PCB for the true bypass wiring like in this JHS pedal:

Or you can include the switching scheme directly on the PCB. I am planning on including it directly on the PCB on the new pedals I am prototyping. It also makes assembling easier and faster.

3. Loose jacks and 3PDT

This is a classical problem. Input jacks and the 3PDT can sometimes become a bit loose, even if you tight them with a pair of pliers. In the worst case scenario, the nut or the bolt can be lost in the process, and the pedal would be quite difficult to use if the input jack or the 3PDT “enters” inside the enclosure… It is really easy to fix, but it is a very common problem, and quite boring to repair because the customer would have to send it over (or I would have to send screws to repair it) just to fix a loose jack. There are two ways to avoid this: either your tight it a lot with a pair of pliers, either you can include jacks directly on the PCB.

However, it has one downside: if the jack input is not working anymore, it is quite boring to replace because dessoldering and ressoldering of the jack is not easy. So, do not forget to use high quality jacks like Neutrik NMJ6HCD2, and not to overcrowd the PCB around the jacks to make dessoldering possible.

I am designing my first “commercial” pedal, and I plan to include the jacks directly on the PCB. It avoids a lot of wiring (reason 2), and prevents loose jacks.

4. False contacts

If you let your PCB “free” in the enclosure, or just wire it without solid core wire (bendable wire), the circuit board can move in the enclosure. Sometimes, it can create false contacts that are quite boring to fix because you never know where it comes from. Also, it happens a lot with veroboard, where the copper side can make false contact with the bottom of the enclosure. The classical "spaghetti wiring" of beginners is also quite dangerous for that...

My recommendation would be to use PCB mounted potentiometers, which make the PCB fixed in the enclosure. If you are using a veroboard, use solid core wire to make the wiring, so you can bend it and try to fix the veroboard in the enclosure. But my ultimate recommendation would be: do not use veroboard. Honestly, it increases the risk of mistakes (misplacing components on the boards, complex wiring…), and can create false contacts easily. A PCB does not cause all this problems and is much more reliable in terms of assembling. This is why I use mostly PCB in my pedals now.

5. Component failure

Actually, I have never seen a component failure per se. Most of the failure I observed resulted from a power supply mistake. The most common case is with MAX1044 (voltage inverter / voltage doubler IC), that can only accept 10V maximum. If someone tries to apply an 18V voltage for instance, the chip simply stops working. Another thing that happens is when someone uses an inverted voltage on a pedal using a normal voltage (polarity inversion). Usually, the diode that protects the pedal from it usually just burn / melt and has to be replaced. Here is an example of a melted diode:

For the MAX1044, I use a socket so it can easily be replaced. For the diodes, I use a “long legs” package on my PCB so I can just cut the legs of it, which makes dessoldering easier. Also, SMD components are much more difficult to replace, so I would advise to avoid it.


There it is! This are the 5 main points I noticed concerning guitar pedal failure. I am sure that you can spot other things that make your pedal fail, do not hesitate to tell me by posting a comment!
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Big Muff mods and tweaks

I recently noticed that a page I referred to a lot just disappeared from internet... It is the Big Muff mods and tweaks page that was deleted recently.

Fortunately for us, there are some "internet archives" website that keep it alive for a while. In order to keep it alive, I added it here. I also added a list of personnal mods that work quite well, and some notes about mods I already tried.

Easy mods

Diodes mods

The Big muff contains 4 diodes (2 pairs of diodes), that clip the signal to create gain, and compress the signal. Changing these diodes can change the compression and gain of the pedal drastically:

• Silicon diodes: these are the original diodes used in the Big Muff. Usually, they are 1n4148 type diodes, and gives the Big Muff reference tone: gainy, compressed yet crispy and tight distortion.
• Germanium diodes: germanium diodes will cut the sound more. You will have a more gainy, more compressed saturation, but also you will loose quite a bit of output volume. No germanium diodes were used in original Big Muffs.
• LEDs: LEDs are also diodes and can clip the signal. Red diodes clip more the signal compared to yellow, blue ones. There will be less gain, less compression and also more volume output. It gives to the Big Muff a nice "overdrive" feel, with a bit more dynamics. Note from Coda Effects: I tried it on this Big Muff variant, I really like it! It gives a lot of dynamics to the muff.
• FET / MOSFET: if you tie together the drain and gate of FET / MOSFET transistors, they will behave like diodes. Sound is similar to silicon diodes, a bit smoother.
• Remove the first pair of diodes, and you have got a Colorsound Supa Tonebender! The unit will be louder, with more bass, but still quite compressed. Great trick for bass players.
• Remove the two pairs of diodes: great trick! By removing the diodes from the unit now sound if fed back. Result: more volume (LOUD!), less compression, less gain and a more open (overdrive) sound. In my Dolmen Fuzz, I removed all the diodes with the central position of the switch: massive spurry sound!

A good way to see what is your favorite combination is to use sockets for the diodes. You can also use switches to change the diodes. Here is an example with silicon diodes and LEDs :

Works really well and it gives you multiples choices. With 2 of these on-on-on switches you can choose between no diodes or 2 different diodes set for each gain stage!

Emitter mod

Each transistor's emitter of the gain stages of the Big Muff is linked to the ground by a resistor (either 100R or 390R, R12 & R16). Removing the resistors will increase the "gainy-ness" of the pedal, increasing the resistors will lower it.

Resistor mod Each of the gain stages has a limiting resistor on the start of it (R8 & R13). These are 8.2k (8k2) or 10k in different models. By diminishing these values the unit gets more gainy. (Note from Coda Effects: beware! There is a typo on the original Big Muff mods and tweaks text. Diminish it for more gain)

Creamy Dreamer

Basically the combination of the Emitter mod and the Resistor mod.

Noise gate mod

This mod will quieten the Muff while not playing, thus a noise gate. To do this, add a 100k trimpot (wired as a variable resistor) parallel to the 100k to ground of the second gain stage (R14). The trimpot can be adjusted to taste to get the max noise gate effect.

Coupling caps mod

The Muff has a lot of coupling caps (C1, 3, 4, 7, 16, 12 & 13). Coupling caps are next to the block of DC also a way to set the frequency response of the unit. 

Enlarging these caps give the unit more bass, making em smaller give the unit more treble. Experiment with em. Also the sort of caps can make a difference in noise, feeling and authenticity. Old Muffs used ceramic coupling caps; using film caps here won't give you the same sound

High roll-off mod

Notice those small ceramic caps on 3 of the transistor stages? They are used to roll of excessive highs. Normally they are 470 pF (C2, 5 & 8) but larger values roll of more highs. You can also remove em for a great result.

Clipping caps mods

Next to the diodes is also a cap placed (C6 & 9). This cap determines the frequency band the unit clips. Enlarging this cap will make it clip more low notes, make it smaller for more high end clipping.

Transistor mods

The Muff uses four transistors and the type and choice of these transistors will affect the sound greatly. The higher the gain, the more the unit will focus on the high end / treble. Some known examples:

• The Russian Muff uses E type transistors (newer ones use BC549C's though) which has a Hfe of around 500. I used BC184's as a great replacement of these transistors.
• The NYC Muffs usually use 2N5088's or BC550's with a Hfe of around 800.
• The Little Big Muff uses 2N5962 with a Hfe of around 1500 - 2000.

The Russian sounds darker due to the low gain. Knowing this, we can change the sound of a muff greatly by replacing the transistors. Small tip: use sockets when changing transistors. This way the transistors are not damaged by the soldering and swapping is much much easier. Some nice ones:

• 2N5133's: used in Triangle ones (the NOS versions tend to sound even better then newer ones) as FS36999's. Very nice sound, smooth, warm, open.One of my favs! Note from Coda Effects: I would not use these ones. They are really rare and expensive. I am not sure that they really sound better... I would try to find something similar in hfe (around 100-400).
• BC239's: also used in a bunch of Muffs around. Slight less gain as the above named but this gives the Muff quite a nice touch.
• 2N5087's: PNP transistors instead of the above named NPN (more usualble). To use these you need to reorient some of the caps and change the + and - of the battery (called positive ground). Although they must be identical to 2N5088's they were used in some old models and do sound different.
• BC141's: ultra low Hfe (around 100) and not suited for anyone out there. More bass, less gain but a very different sound.
• MPSA13's: ultra high Hfe (around 10.000). Nice touch for some more gain.

Experiment! Use four of the same transistors or try to mix. For example I like a Muff with 5133's for the clipping stages and MPSA13's for the buffer stages.

Note from Coda Effects: I also experimented with a few transistors, here is my feedback about this:

• The first transistor is the one that will define the most of the gain of your unit. Higher hfe = more gain, but also more trebles... I tried a few ones:
• 2n5089: high gain, but also gives a "gritty" touch to the muff that I do not really like. Also quite noisy
• 2n5088: nice sound, gainy unit, but less noisy and agressive trebles than 2n5089. I really like it and use it often.
• 2n2222A: low gain, gives more bass and smoother sound. Beware: polarity is reversed compared to 2n5089.
• MPSA18: extreme gain! I would suggest to increase emitter resistor to limit gain (especially for noise issues), but you can have a nice "doomy" muff with it!
• 2n3904/BC549C: great for a low gain Muff.

• The two transistors of the gain stages play a bit more with compression. I usually use low hfe. 2n2222 are really nice for this use. 2n5088 can also do the job.
• The last transistor will define the final output volume of the unit. I like to have quite a lot of output volume, so I prefer to use high hfe transistor for the last stage, like 2n5089, or MPSA18.

Feedback mod

This mod is also not for anyone. It will give the Muff a weird drone note that will interact with the notes played resulting in octaves (up and down), nintendo sounds or a huge MUSH. Can sound quite nice and interesting!!!!! The mod is done with a feedback loop: connecting two points together and letting signal flow back. I found two of these loops in my Muff (note: more can be there; try for yourself!)

1. Connect the emitter of Q3 with the emitter of Q2 through a switch (so you can turn the loop off). The sustain will be on full when this mod is engaged.
2. Connect the collector of Q3 with the collector of Q1 through a switch. The sustain now can be varied by the sustain knob.

Great addition: add a 1M potmeter in the loop (wired as a variable resistor) or, even better!!, a LDR (light dependent resistor). With the latter, you can control the amount of feedback with the light on stage / with your foot shading the LDR from the light. Cool!

Note from Coda effects: this is really cool, but I will suggest to use a momentary footswitch. If not, you can be quickly bored with the noisy issues that will rise from this mod. However, from times to times (beginning of a song), it is a killer mod to use!

Pictures:

NYC muff:

Russian muff: (Note from Coda Effects: these units are getting rarer and rarer, I would not modify it)

Tonestack mods

The Big Muff Pi is legendary due to his tone section; only one knob to select between a bass, treble or in-between setting. The overall sound of this tone knob is the loved / hated mid cut.

Some Versions:

• Triangle version: R1=33k, C1=4n, R2=33k, C2=10n;
• Ramshead version: R1=33k, C1=4n, R2=22k, C2=10n;
• 1975 version: R1=39k, C1=4n, R2 = 22k, C2=10n;
• 1977 opamp version (1): R1=5.6k, C1=100n, R2=1.2k, C2=120n;
• 1977 opamp version (2): R1=8.2k, C1=100n, R2=1.2k, C2=120n;
• Green Russian version: R1=20k, C1=3.9n, R2=22k, C2=10n;
• Late model: R1=39k, C1=4n, R2=100k, C2=10n
• Reissue version: R1=22k, C1=3.9n, R2=22k, C2=10n;
• Little Big Muff version = reissue version.

And then some different mods:

• Swollen Pickle: R1=33k, C1=3.3n, R2 = 22k, C2=47n;
• Flat mids: R1=33k, C1=5.6n, R2=33k, C2=5.6n; 

Tone stack bypass mod

By bypassing the tonestack the tonestack has no influence anymore on the sound thus does not color the signal in it's own way. Great way to get a more middy tone from your Muff. As the tone stack also cuts volume you get a huge volume increase

Tone stack complete mod

One of my most fav mods. Remove the tone stack altogether from the Muff and place a three band EQ circuit in it's place. Works like a charm and gives you more control over the sound! I also once added a Boss GE-7 in this place to give total control over the sound.

Read my post about the Big Muff tonestack for more infos about how the tonestack works and what mods you can do.

Bonus mods (Coda Effects)

Here are other easy mods and tweaks that can give a nice touch to a Big Muff:

Input Resistor / Capacitor:

The input resistor (R1) and capacitor (C1) defines how much signal enters the pedal, ie the overall gain of the unit. It also forms a filter that will allow some frequencies to go in or not.

Increasing the value of the resistor will lower the gain, and lower treble content of the pedal.
Increasing the value of the capacitor will increase the amount ot bass and the overall gain of the unit.

I like to use a switch to choose between a high gain bassy setting, and a lower gain treblier setting.
A smaller value in C1 also helps reducing noise. I used this mod on this Big Muff for instance.

LPB1 before the muff circuit

Adding a LBP1 before the muff circuit can allow you to add an extra gain / bass amount to the muff. It really add some "heaviness" to the distortion. You can do it on a veroboard, with a trimmer or external gain potentiometer. I want to use the PCB I made recently to try this mod. The musket from Blackout Effectors uses this trick. With a simple 3PDT wiring, you can make it activable or not.

Germanium transistors in the distorsion stage

It can smoothen the Big Muff a bit, but remember to have a high gain last stage to recover enough volume. This is used in the Hoof fuzz from EQD. I am not super found of this mod, but you can try it out if you want! Remember to use NPN germanium transistors.

Voltage starver mod

You can emulate a dead battery, that will give a very peculiar sound to the muff: it cleans up a bit, and the circuit starts to sound "gated", and "stutters" a bit because it does not have enough power to work correctly. I would suggest to use this schematic:

 

Just connect the output voltage to the voltage input of your Big Muff.

18V Muff 

Beware: I never tested it on a EHX, and I do not know if the stock pedal can handle 18V... If you have already test it, tell me. However, if you have made a clone with capacitors that can handle 18V or more, you can try to use a MAX1044 as a voltage doubler to supply your Big Muff with 18V instead of 9V!


Here it is! I hope that you liked it, good luck with experimenting!
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The different types of Fuzz

Fuzz is one of the most emblematic guitar effects. Satisfaction (The Rolling Stones), Purple Haze (Jimi Hendrix), Think For Yourself (The Beatles)... The number of great songs incorporating this effect are countless, and have progressively transformed the Fuzz effect into a reference in the electric guitar world!

Today, we can find a lot of different fuzz, with multiple variations around the same circuit... In order not to be lost in this mess, I wrote a small overview summarizing the different types of fuzz that you can find. Of course, it is not an exhaustive listing, I tried to recapitulate the main fuzz, and modern and "boutique" variations that can be found today... Make your choice!

1. Gibson Maestro FZ-1 (1962)

This is the first fuzz ever invented! Originally, it was intended to imitate brass! To give you an idea of how it sound, it the fuzz used on "Satisfaction" of the Rolling Stones.

It has a nasty, sax-like sound, quite aggressive in the treble range. It is a harsh, dirty sound that can feel almost like a ring modulator in last strings! It is a very peculiar sound, very "vintage-sounding" (well, of course, it is from 62!). To be honest, I do not really like it, but I think it can be used a bit in some styles like garage rock or psychedelic rock.

Of course, the original pedal is extremely rare and expensive... (I had one to repair recently!) The Boss FZ5 emulate with a numeric algorithm the Maestro fuzz, and clones are pretty rare (you can find clones in small boutique companies), because of the weird sound that makes it a bit special... Gibson did a reissue at some point, but it was also quite expensive, and had the downsides of the original pedal (size, no power supply input...etc).

2. Sola Sound Tonebender Mk1, Mk1.5 and Mk2 (1965 et 66)

Created in England in 1966 to compete the Gibson Maestro (which was too expensive to import...), this fuzz quickly became a reference. The MK2 version was used by many english rock musicians in the 60s, like Jeff Beck or Jimmy Page for instance. It has been also been copied by many brands: Marshall Supafuzz, Vox Tonebender are examples of fuzz "heavily inspired" by the Tonebender.
 

It has a more classic fuzz sound, loud and powerful, with quite a lot of saturation. The saturation can be modified with the volume knob of the guitar, like with Fuzz Faces. The sound is warmer, softer than the aggressive Maestro sound, with quite a lot of mids. Basically, it sounds a bit like a Fuzz Face, but with more saturation and a bit more aggressive, close sometimes to a distortion.

It has been clone, modified and reproduced by many builders: D*A*M (who makes incredible replicas), Earthquaker Devices Tone Reaper, Fulltone Soul Bender, Basic Audio Scarab Deluxe, JHS Bun Runner, Ramble FX Twin Bender...etc.

3. Fuzz Face (1966)

This THE Fuzz, the most emblematic fuzz effects with its famous round and red face (well, gray at the beginning). Used by Jimi Hendrix, it became rapidly famous! Conceived in 1966 by Dallas Arbiter in England, it used germanium transistors at first, which were later replaced with silicon transistors, more stable. Read my article about the fuzz face circuit here.

The sound of this fuzz is characteristic: very soft, warm and round, it has a very "creamy overdrive" feeling that evokes almost always (especially if you have a Stratocaster-type guitar) the sound of Hendrix. It also responds very well to the guitar volume knob: by turning down this knob, you can go back to an almost clean sound! Versions with germanium transistors are ideal for this, but are less stable (sensitive to temperature, demanding about the transistors characteristics). It is less saturated than a Tonebender. This is really a classic fuzz, easy to use and very good sounding

The Fuzz Face is still produced by Dunlop (with a lot of versions: mini versions, germanium and silicon versions...etc.), but many builders took the opportunity to build their own Fuzz Face version and make original versions: Analogman Sunface (a great replica of the vintage Fuzz Faces), that I cloned here and here, Fulltone 69, JHS Pollinator, Boss FZ3, Chase Tone Red Stardust... are all modified Fuzz Faces.

4. Roger Mayer Octavia (1967)

With its strange spaceship shape, the Roger Mayer's Octavia will not leave you indifferent. Roger Mayer was Jimi Hendrix's guitar tech (...yep!), and has created and modify pedals for the master... The Octavia is one of them.

One of the things that make this pedal unique (beyond its weird look), is the fact that it produces an upper octave sound above what you play! This octave effect is more pronounced around the 12th fret, so it is more hear-able during solos. It has quite an aggressive sound, which can be slightly dissonant (because the octave is never perfet in terms of pitch). Here again, some Hendrix's song are representative of the sound of this pedal, as the solo Purple Haze or Fire.

Roger Mayer is still producing the pedal, but it also has been cloned and modified: Fulltone Octafuzz, Catalinbread Octapussy (I love this name), Electro Harmonix Octavix...etc. Which seems to please Roger Mayer a lot, as he put on his website this beautiful quote: "Those who can invent do, those who can't invent copy" (Angry Roger is angry, but well, it is understandable)

5. Univox Super Fuzz (1968)

Well, this is a personal favourite, for me this fuzz is the evillest fuzz of all, a monster in a pedal enclosure, a true Pandora box! This fuzz, invented in 1968 by the Japanese company Shin Ei (which became Univox later), has not only a killer look (well, from the second version in 1970), but is also the most violent an loudest fuzz ever! It has been used by Pete Townshend during the Who's live performances, and has been re-discovered in the 90s by many stoner rock bands, some of which used it almost on every song like Fu Manchu!

Like I said, this Fuzz has an over saturated heavy sound. There is a lower octave that is added to your tone and make it heavier, and an upper octave, quieter than on the Octavia, that is hear-able around the 12th fret. To give you an idea of the apocalyptical sound of this pedal, listen to any song of Fu Manchu. (check Cyclone Launch for instance)

Unfortunately, the production of this wonderful pedal was stopped. Boss produced a clone in 1993, the Boss Hyper Fuzz FZ2, which had some success in the stoner rock / doom circle, but is not produced any more. Today, Behringer produces a cheap clone, and some boutique builders make clones (Wattson Super Fuzz (replica of the 68 version), Solid Gold FX Formula 76). Producing a fuzz respecting the spirit of the original Super Fuzz (sound and look) is one of my current projects. If you're interested, please email me for details.

6. Electro Harmonix Big Muff Pi (1969)

This is an absolute classic created in 1969 by Electro Harmonix: the Big Muff Pi. This pedal is still produced, an had many different versions (Deluxe, Russian, Triangle, Ram's Head...). It has been used by a lot of different artists because of the sound it has, and especially the almost infinite sustain it gives to your tone. David Gilmour (Pink Floyd) is a well known afficionado of the Big Muff.

Comfortably Numb's solo is a good example of what kind of sound can be expected from a Big Muff. It is a heavy, saturated sound, but still compressed and smooth, that gives a nearly infinite sustain and crazy harmonics. The tone potentiometer allows to go from a trebly aggressive fuzz to something warmer and bassy. One of the characteristics (and weaknesses) of this fuzz is the lack of mediums that the EQ create. You can disappear in a mix because of that. To avoid this, David Gilmour was using it with an overdrive that was bringing more mids, and today, there are versions of the Big Muff with a different tonestack that have been created to avoid this. If you are interested, I wrote an article about the Big Muff circuit.

This pedal is the clone's queen, probably the most cloned pedal ever! There are hundreds of versions of the Big Muff, as it is a very well documented circuit, and very tolerant to modifications. Pete Cornish G2, P1 and P2, Skreddy Mayo, Way Huge Swollen Pickle, Mojo Hand FX Colossus and Iron Bell, Blackout Effectors Musket, Black Arts Tonework Pharaoh...Etc Each "boutique" builder has its own version of the Big Muff, and I already made a few Ram's Head Big Muff myself!

7. Shin Ei companion Fuzz (1970)

Lets finish this list with an original rarity, the Companion Fuzz, created in 1970 by Shin Ei (again). If I put this pedal in this overview, it is that despite its rarity, it really has a very special, unique sound!

It produces a "chainsaw", buzzy, nasty sound! It has a very harsh and raspy sound that is really recognizable. This pedal has been used by some psychedelic rock bands, and more recently by Dan Auerbach from the Black Keys for the dirty sound that it makes... It is really an unique sound, either you like it or you hate it!

Due to this weird sound, demand is quite low for this kind of effect, and re-editions or clones are quite rare. The original is of course not produced any more (and reaches crazy prices on ebay), but Earthquaker Devices recently issued a clone: the Terminal Fuzz. Some small boutique builder still make clones of it. 

8. 1970-2010: what happened?

Where did all the innovations of the fuzz pedal go during this period? The 70s marked the beginning of overdrives, that gradually replaced fuzz, both in music and guitarist's gear. Fuzz was replaced with amp and overdrive saturations. Indeed, since the beginning of the 70s, amplifiers (finally!) have a master volume, and fuzz are no longer necessary to have a distorted sound. New musical genres that emerged at this time, like hard rock, are more into heavy saturation from the amplifier than the "weird" saturation of fuzz.

However, in some genres played irreducible musicians, fuzz still holds out against overdrive and distortion invaders. Stoner rock guitarists rehabilitate fuzz effect to produce heavy saturated sounds (Kyuss, Queens of the Stone Age, Fu Manchu...). Some indie bands make fuzz become their sound trademark (Smashing Pumpkins, shoegaze players...). During the 2000s, with the arrival of bands inspired by the 60s (like the White Stripes and others garage rock bands), fuzz resurrects and becomes a classic effect again. Other artists use it in a new way to create new musical landscapes, and make it popular again (like Matthew Bellamy and his Fuzz Factory)

Traditional and boutique manufacturers modify and enhance vintage fuzz by making them easier to use (9V power supply input, smaller size), less noisy and more stable.
Some builders innovate and create entirely new circuits, most of the times completely crazy: Death by Audio (with the Fuzz War for instance), Devi Ever (Hyperion, Soda Meiser) or Zvex with the Fuzz Factory. Others invent new designs with more classical sounds: Wampler Velvet Fuzz or D*A*M Meathead for instance!

Personally, I am a huge fan of fuzz. The Super Fuzz, the Big Muff and the Fuzz Face are must-try pedals for me. Moreover, fuzz are simple pedals that are easy and fun to make, and that can easily be modified and customized! I really advise you to try to make one... The Big Muff is the perfect pedal to begin with (with a PCB if possible), even for a beginner, and can be modded really simply (the circuit is very tolerant to modifications).

Here it is ! I hope that this article gave you a good overview of the different fuzz that exists, so you can choose the one you like the most! Do not forget that this is not an exhaustive list, and that many other fuzz exist... The quest for the ultimate fuzz is nearly infinite (gotta catch them all!)

Do you have any question? Post a comment!
You like this article? Thank me by liking the Coda Effects Facebook Page.


To go further:
"Fuzz timeline" from the Big Muff page
Another Fuzz timeline by Hewitt's garage
Fuzz Face history : a nice video about Fuzz Face history.
Maestro Fuzztone history: great article from vintageguitar.com
History of Tonebenders by D*A*M

Troubleshooting guide for guitar effects: the audio probe

The audio probe is a simple, yet very useful system that allows you to check where the problem is when a circuit is not working. You tried the simple debugging technique, and nothing stands out? The audio probe will solve it!

Here is the schematic:

(most simple schematic in the world, just before the Strymon favorite switch)

It is a simple 1/4" jack input, a 0.1 uF capacitor (here I used a Panasonic SMF), and a wire that you have to connect to the ground. You can then use a jack cable plugged in the jack input, connected to your amp. Usually, I use a looper to always have something on the input of the circuit.
Beware: set your amp on a very low volume setting. When using the audio probe, you can encounter really large signals when going through the signal path. It can be source of surprises... (or deafness...)

How to use an audio probe?

The 0,1uF capacitor will not allow direct current to go through it. Thus, you will only hear alternate current signal that is your guitar signal. You did not know that your guitar signal was an alternate current? Read my post about guitar signal.

You need an input signal to go in the circuit. Generally, I use a looper (Jamman, Ditto) to have a guitar signal going in. You can also use a signal generator, or anything else : keyboard, CD player, or someone else who will strum the guitar while you use the audio probe.

Then, just follow the signal in your circuit: put the tip of the 0.1 uF capacitor on the input of the circuit; you should hear the guitar signal at the same volume than at the input. Then move component by component, following the path of the guitar signal.

If we take the Fuzz Face as an example:

 

You will put the tip of the audio probe first at the input of the 2.2uF capacitor (positive lead), then on the output of the 2.2uF capacitor. The sound can be slightly modified (this is also a great tool to see what is the role of each component!), but should still be here. Then, you will go at the base of the first transistor (Q1), and check at the emitter of Q1 (signal should be louder)...etc. Just follow the path of the signal!

If you hear the sound before a component, and nothing after, you know that it is this component that is faulty! There are several options: it can be a cold solder joint, a false contact, or a damaged component.

It is really a great tool to decipher which component is the problem in your circuit, or if there is a false contact somewhere (very common with stripboard!)

Moreover, it can allow you to understand very intuitively what is the role of each component of your circuit. Using the audio probe, you also have to look at the schematic of the circuit, which is a good thing compared to copying the guitar fx layout scheme. It is a very good way to learn!

Hope that it helps!

If you liked this article, thank me by liking the Coda Effects Facebook page!

Any questions? Suggestions? Post a comment! 

To go further: 

Circuit debugging page of diystompboxes

Top 5 guitar pedal facts that should light a « warning » sign, from a DIYer

Recently, the "boutique" pedal world was shook  with many scandals and  scams, combined with more than questionable business strategies. Taking advantage of the over trust of people towards small local companies, some manufacturers allow themselves the worst scammers. What could we do to detect rogues builders among the honest small companies manufacturers? Here are some tips!

1. Do not buy guitar pedals with goop (and yes, that includes the mighty klon). Goop is a kind of black resin that is put on the components of a circuit. Builders often say that “it protects the components” or “avoid oxidation”… This is not true. Most of the time, it is used to hide that the circuit was stolen from somewhere, or to prevent people from copying it (but it does not work as people manage to remove it). The biggest problem is that you cannot replace a component because it is melt in this black disgusting soup. So goop = big trust issue and possible irreversible failure for your devices

 Who spilled oil on my Klon?

2. Do not buy analog overdrive / fuzz that are above 250 euros (except for collectibles ones). Electronics are cheap. Most of the time, and especially for distortion / fuzz / overdrive pedals, the most expensive part is the enclosure! When above this price, ask yourself questions before buying… Of course there are exceptions, but do not whine when you will discover that your 350 euros Jan Ray costs approximately 50 to make! A very expensive pedal will not always sound better than a cheap one (cf point 5). Dont get me wrong, it is normal that a builder makes some money out of his business (you have to live!), but sometimes it is just too much I think. This does not apply for numeric pedals, where more development time is needed, and use microcontroller that are quite expensive.

This is completely insane. A fuzz face

 (so 10 components) for 400 dollars?

3. Do not spend a lot of money for “top quality components”. Today, the price difference between a correct component and a high quality one is really low. Basically, between a standard electrolytic capacitor and a high end one, there will be near 0.30 euros difference maximum! HiFi capacitors are quite useless in guitar effects are there are used to be ultra transparent, but are not really appropriate for guitar pedal use: you do not want a total and extremely precise reproduction of the original signal, do you? A standard wima MKP2 is transparent enough! Even rare and vintage transistors often have alternatives that are cheaper and totally usable. So do not waste your money on components if you are looking for a particular sound. It is only valid if you are looking for a replica for instance.
 
4. Check the inside before buying it. Everyone should be able to know exactly what he is buying. Do you buy a computer without checking its specs and components? Do you buy stuff without knowing what they’re made of? No, of course! So it is the same with guitar effects! Ask to look inside or search for pictures on the web to know the global complexity of the circuit, what it is inspired of...etc Also, SMD components indicates you that there is very little chances that the circuit was hand assembled.

 Left: Joyo Ultimate Drive (cheap OCD clone)
Right: Freekish Blues Alpha Drive: a rebranded Joyo! 
(with goop, remember the first fact?) 

5. Do not trust the hype, trust your ears, not you eyes. Most of the time, people recommend an effect upon another one because it “sounds better”. But when blind tested, most people are not able to tell anymore what sounds the best or even which is which. Your brain is modifying a lot what you are hearing depending on what you see! A psychosomatic effect makes your brain actually believe that the most expensive pedal sounds better. An A/B box can be a great investment to blind test pedals to hear for real whether they really sound that much better or not. Try to test some pedal with a random switching between the 2... Most of the time it is impossible to tell the difference, or to tell which one sounds the best! They can sound different of course, but generally speaking, such a blind test is full of surprises!

 

Could. Not. Resist.