Ground loops and guitar pedals

Yesterday, I received an email from a beginner that decided to make his first guitar pedal. I always enjoy this kind of emails and answering questions is part of the game. This time, he asked me a question that I had several times: "my circuit is noisy, could it be a ground loop?"

Ground loops are part of the legends and myths around DIY guitar pedals. When asking about noise in a setup, it is the most common answer, and is supposed to be the main cause for hum, hiss or other noises that you can have on your first circuits.

Montagne Tremolo PCB

So I decided to write a post about it, starting from the begining:


Development Hell: multiple fuzz pedal

Today, I am going to introduce the concept of Development Hell: it is a special place where projects stay when they need a lot of fine tuning before properly work. Unfortunately, I have a few projects that are still burning there, like the one I am going to present today.

It is a multi-fuzz machine! I always felt that a lot of Fuzz are quite a "one trick pony", they have a very characteristic sound that can be modulated by mods, but still sounds "like a fuzz face", "like a big muff"...etc. Moreover, fuzz are usually quite simple circuits, and I find that allowing one spot per fuzz on a pedalboard can quickly be space-inefficient.

So I decided to create a multi fuzz pedal, with no more than 3 different fuzz inside : a germanium Fuzz Face, a Muff Fuzz and a Companion Fuzz, which should provide the 3 main "flavors" of fuzz in this world: a classic warm, soft fuzz face, a "chainsaw", very raspy Companion Fuzz, and a compressed and heavy Muff Fuzz.

On top of that, I added an upper octave generator that allows to combine it with any fuzz, with a potentiometer to adjust the amount of octave. It is based on the Green Ringer circuit, which is a small, but efficient analog octaver circuit.

And of course, I made it fit in a 125B enclosure...

Here it is in its current form:



Hakko FX888D: a $100 high quality soldering station

Let's face it: your good old soldering iron is not always the best pal to work with.

I had some troubles with mine: no support to put it when I busy doing something else than soldering, which can be quite dangerous if it falls or burn something. Moreover, the power cord was quite short and not very flexible, so it was not always easy to find a good "spot" for it in order to be perfectly comfortable. Finally, it takes a long time before getting hot enough to solder, and 30W is sometimes a bit low to solder big potentiometer or jack legs.

So I decided to invest a bit in a soldering station.

After reading a lot on the web, I have found this little gem: the Hakko FX888D, a Japanese soldering station that was recently replaced by the FX888DX version you can find for around $150 on Amazon

Here is mine:
Hakko FX888D

Vintage Maestro Fuzz-Tone FZ1-A (1966)

The Maestro Fuzz-Tone is simply the first fuzz ever! I felt a bit like an archeologist when inspecting this effect ! Someone gave me this one for repair, experiencing some issues with the built-in jack and the switch. Here it is:

Maestro Fuzz-Tone FZ1-A 1966

14 electronics suppliers for guitar effects (with pros and cons)

Finding good electronics suppliers is a key issue when building guitar effects professionally. Indeed, they play a huge role in traceability and quality of the components (where the components come from and what they are exactly), and also the price of these components. Sometimes, they can also add delays if they are bad with handling orders and shipping it quickly.

Goods electronics suppliers are the root cause of a good build quality for a pedal builder.

With my crowdfunding project, I have an intermediary position. I cannot order directly from manufacturers (because I would have to order thousands of units at least), but I can order from electronics wholesalers!

Already 95% of the components have been ordered, and I already received quite a lot of parts! Here is a picture of the switches I got this morning (more pictures will follow in a next post):