AC Noises Urla

“Urla” is an Italian verb which means “scream” in second person imperative (tu, urla = you, scream).

A loud, aggressive and experimental device which consists in 2 effects in 1 pedal unit, the URLA is a CMOS fuzz in front of a synth-based dual resonant filter.

CMOS Fuzz:

A CMOS chip works with digital logic (1, 0).
Compared to the transistor based fuzz circuits (it doesn’t matter if germanium or silicon), in a CMOS fuzz there is no “in-between”, no “dynamic range”, no “vintage tone” or anything like that. There are just 1s and 0s, so no matter which kind of waveshape you put into it: the output will always be square wave with no adjustable gain neither since the square wave is as distorted as it can get.

The URLA obviously makes no exceptions and it provides an overdriven, glitchy and gated fuzz sound with a decay that dies abruptly (but still allowing to sustain each note thanks to a bass boost stage that we put at the very beginning of the signal path).

It offers 2 controls: VOLUME and BLEND.
VOLUME (fuzz)
Adjusts the output level of the fuzz.

BLEND:
As the name suggests, this control allows to blend the fuzz sound with the original signal placed in front of the URLA. Clean guitar tone is probably the most basic example in that sense but no doubt the bravest sonic adventures could find plenty of different as exciting solutions (e.g. as “wall of sounds” enthusiasts, we do love to place a shimmer reverb in front of it or some modulation as well to create different kind of textures). Being a fully analog jFET blend, it goes from almost completely DRY (counterclockwise) to 100% wet signal (clockwise).

DUAL RESONANT FILTER:
This is the second effect placed in the internal signal chain of the URLA and it consists in a faithful replica of the analog filter section of the glorious Korg MS-20, simply our all times favorite vintage monophonic synthesizer.

It’s an HIGH PASS filter connected in series with a LOW PASS one, both adjustable with their relative controls of CUTOFF and PEAK. Also, we added a dual potentiometer to control the VOLUME of both, which is pretty useful in order to dial with other output levels in chain (including the internal FUZZ placed in front).

VOLUME: (filter)
Sets the output level of the dual filter.

CUTOFF:
These knobs allow to decide where the frequencies (high ones by LP, low ones by HP) have to be cut. No doubt they’re the most exciting controls of the URLA.

We placed those on the external sides of the pedal surface exactly because of that: you’ll love messing up with those as much as possible by exploring the wild excursions of both. In fact, depending on the place of their relative PEAK knobs, they can go approximately from 50hz to 15kHz.
Note: since the filters are connected in series (HP into LP), you’ll completely mute your signal by turning the LP cutoff fully counterclockwise.

PEAK:
While cutoff allows to remove frequencies (harmonics) from the incoming audio signal, their respective resonance allows to have an additional controlled amplification of that cutoff frequency, creating a secondary peak form and coloring the original pitch.
The resonances of the original Korg MS-20 are well known for their pretty wild and loud nature due their tendency to create a microphonic feedback at extreme settings. URLA makes no exceptions, so USE THESE KNOBS CAREFULLY because they really make your amp scream at high level!

EXPRESSION:
We’re not going to lie: if you’ll not play the URLA with an expression pedal (by using a TRS cable) to control the cutoff of your favorite filter (HP or LP it’s up to you: just place the EXP toggle switch where you prefer), you’ll probably miss more than the 90% of the fun.
For that reason, our friend Luca Romanelli from Mastro Valvola (the same guy who wrote the code for the RESPIRA’s shimmer) designed an expression input which works correctly with ANY expression pedal on the market.

But there’s more: when the expression pedal is plugged into the URLA, you can still set the minimum (the starting point of the parameter you want to control with the expression pedal) by adjusting the relative cutoff knob.

As aggressive as experimental-friendly, URLA is our tribute to all the industrial, noise and alternative artists/records that made our world a better place to live.