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Eurorack

johnathan
November 28, 2024
EFCcv Eurorack


Electron Fuzz Custom eurorack module

Price: $299 (reg price $319)
Domestic shipping: Free
Aprox. International Shipping: $24-$39 (we cover half the USPS priority international shipping.)

In Stock Feb 2025

 

28hp

82ma @ +12
6.25ma @ -12



EFCcv Eurorack colors



***Please read***
We have a limited number of Nuclear Winter White EFCcv euorack panels available. These are only sold here on the website and not sent out to our retailers. Once they are gone it may be a while before we make more. And now back to the original content…

Previously: The Electron Fuzz Custom into 100% full eurorack format. This is the full production run. Laser cut aluminum panel. Built by organic free range Portlanders. Lots of videos on Instagram. Click here to browse my personal RML account.

The eurorack module is essentially the same as the “EFCcv euro” pedal with a couple of slight modifications.

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  • I’ve added the GPI (Guitar Pedal Interface) input attenuation. This lets you bump the input down even lower levels to compensate for the hotter eurorack line levels. It also give you the ability to still use it with guitars and standard line level instruments such as external drum machines and synths like with the original guitar pedal. You can literally patch a guitar right in using the proper 1/4″ to 1/8″ cable.
  • Taking full advantage of the higher voltages available I was able boost the final output of the pedal to full eurorack levels. The “Bleed” (Clean Mix) is now independent of the distortion GPI attenuation. So mix that awesome hi-fidelity signal in with your distortion, or turn it completely off. Its up to you!
  • I’ve included the original “EFC” output. This is a direct tap of the pre-eurorack EFC guitar pedal. The output is muted when in bypass. The output is lower (like the original pedal)  and before the final op amp gain staging. Feel free to plug an output signal in and see what happens. Its an “in” AND an “out”.
  • This version has conventional knobs. Meaning as you turn to the right the volume increases. The original pedal works in reverse. I will likely change that back when we have the manufactured panel. I’ve always felt the reverse knobs helps break out of the
  • IMPORTANT: This is a high gain distortion. It will boost any line noise you feed into it. This is most apparent when the x1000 toggle is engaged. You may think your system is quite until you crank that gain up! It will not insert noise into your system, only amplify noise that is already there. This is a byproduct of distortion pedals and is not something I can filter out without affecting the sound. If you have it plugged in and NOT in bypass mode you will hear your systems line noise. This might be an non-issue since its not noticeable while sound is running through it. Naturally when not using it and nothing is plugged into it you wont hear anything. I just like to remind people there are consequences to your actions. Artificially boosting your gain this much sounds great but is not without its artifacts.
  • It has true bypass just like the guitar pedal. Yeah thats crazy but I left that on for performances.
  • Just like on the standard pedals there can be potentiometer wiper noise. Most apparent when no sound is running though the pedal.

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A couple of demo videos:


•••Eurorack module while still a guitar pedal.

4 CV inputs work on a positive +5 voltage. Safe to run higher voltages in but you wont notice much change past 5volts.

CV Control:

Hurt“, “Pain“, “Feedback OSC“, and “Distortion Out” all have independent CV controls.

Hurt” works as a Hi-Pass. “Pain” works as a low pass. Both of these tone controls are tied to gain stages. Changing these also affect the amount of gain passing to the next gain stage. This produces a more chaotic form of tone control and a wide range of textures. “Feedback OSC” is a noise making function that can produce sounds ranging from low pulses or bit crunch to tunable wha-screaming self oscillation. The tone of the Feedback OSC is greatly dependent on Hurt and Pain controls. “Distortion Out” is the volume of the distortion pedal. It works like a basic VCA. The Distortion Out is independent from the “Bleed Out” that functions as a clean pass circuit. Ideal for mixing distortion with synths or anything from vocals to drum sounds.

The new input impedance knob: reduces the amount of signal hitting the distortion circuit.
Concept: The clean signal pass provides a way to keep the fidelity of the original signal intact while mixing the distorted signal over it.

Function: ***This is a high gain distortion pedal. Please expect it to behave as such. In short it will amplify line noise. Moog products tend to be very clean. Dave Smith synths such as the Pro2 tend to have a higher noise floors. While no signal is being run through it the noise floor will be amplified. If a square wave CV signal is left on you may hear “CV tick” as the transistors switch from open to closed.

More about the Electron Fuzz Custom:

The Electron Fuzz “Custom” is an extremely high gain distortion. Seriously, normal volume setting is at about 10% of its full output potential. Two gain/tone controls “Hurt” and “Pain” give a variety of tone textures and a feedback noise loop can be adjusted to add a very gritty almost 8-bit sound or a squelching scream. (Great for droning or well crafted solos and recording). The extra stomp switch adds 2 more additional gain stages and a boost of high end to the sound. Best of all the distortion oscillates when notes are held adding a new level of expression.

 

The EFC before it was transformed into eurorack:

Here is a great demo video of the non-cv EFC from the “Pedal and Effects” youtube channel featuring Alessandro Cortini of NIN, Sonoio and Modwheelmood.

Please read the brief history of the Electron Fuzz here.

[list_circle]Things I personally enjoy about this pedal:

  • Modulate that crazy feedback OSC
  • Fuzzy to crunchy tones
  • Wide range of possible textures and character
  • Expressive distortion oscillations
  • Feedback noise loop for unusual sound design
  • Extremely high gain for recording direct to your DAW
  • Use with guitars and keyboards
  • VU meter responds to your playing

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The red LED switches on when boost mode is enabled. A convent way to know where you are when playing.

• Knob controls:

A unique approach to tone control…

Hurt: Controls the gain of 3rd gain stage. Lowering the gain will also reduce low end.
Pain: Controls the gain of the 2nd transistor gain stage. Lowering the gain will reduce high end.
Output: Volume/saturation. Take some of the edge off the mix or crank the pain and hurt all the way for a big, dirty, crunchy fuzz.
FB Noise: Adjusts the amount of feedback in the circuit for noise making. Creates a weird octave mod fx.

• Switch controls:
Low cut toggle: Cuts the low end for a slightly less bassy more gated sound.
x1000 gain: On left stomp switch. This takes your sound through an addition 2 transistor gain stages and pushes the electrons way past 11! The booster switch adds a loud and dirty, thrash crunch to this versatile pedal. Incredible for feedback noise and FX textures. Can cause the parasitic frequency oscillation but sounds awesome while playing.
True Bypass: Lets you play through the pedal.

• Meter: Responds to your playing, and reflects first gain stage transistor distortion. Illuminates when active.

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More info on the Electron Fuzz!
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***All purchases done through Paypal. Units are always shipped ASAP. Please note when purchasing from eBay shipping charges may be vary.

****International shipping can vary. Typically I will credit back any difference when your unit is ready and I am able to verify exact shipping to your specific location.

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johnathan
November 20, 2024
GPI (Guitar Pedal Interface)

RML Guitar Pedal Interface

GPI eurorack (PCB panel) $99

GPI eurorack B-stock PCB Panel $85
Domestic US Shipping:
FREE.

Only available with the PCB Panel. I’ll post some updated photos when the new batch arrives.

When evaluating the price please understand the cost factors in shipping which can cost us about $12 +/-  for priority 3 day domestically. 

Options:

About the GPI eurorack module

The RML “GPI” or (Guitar Pedal Interface) is designed to bridge guitar pedal world with modular synth world. An 8HP eurorack unit with two attenuators for sending a reduced signal to guitar pedals for better dynamic response and two pre-amps that boost that lower volume signal (from guitar pedal) back to eurorack levels. Each pre-amp splits the output signal into two patchable outs for creative routing options into other modules.

Power: 10.5mA+/8.6mA-

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  • 2 units per module allowing for use with stereo pedals.
  • Use the pre-amps to boost other low level signals like line level gear. Outboard synths and drum machines.
  • Use the attenuators to reduce control voltages being sent from other modules
  • Plug your guitar right in to the GPI using 1/4 to 1/8 cables
  • LEDs flash in response to the signal being boosted by the pre-amps. A good indicator on how hard your driving the signal.
  • Very low power consumption.

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A couple of random thought on the design:
There are many “Send and Return” modules available, all mono. With this one I wanted to make something available that could handle stereo pedals (or line level gear) without having to buy multiple units. Along the way I decided that having 1/4″ cables hanging off the eurorack seemed bulky and cumbersome so I went with 1/8 (3.5mm) jacks. 1/4 to 1/8 cables have the same construction as eurorack cables and can be found at places like Perfect Circuit Audio at a very affordable prices.

After building the first prototype I quickly found that just using the pre-amp worked great for boosting the Buchla audio level up to normal levels compared to my DPO and Lifeforms. Routing my Moog though the attenuation and into the pre-amp worked like a charm. Having this simple but versatile tool in my rack has definitely been enjoyable. Not only can I now use all those old guitar pedals with my system, but external keyboards I hadn’t considered are now an option.

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