AC Noises Urla – Digital CMOS Fuzz

AC Noises Urla

The AC Noises Urla is a fantastically innovative digital CMOS fuzz. In front of the fuzz is a synth-based dual resonant filter.

CMOS Fuzz

A CMOS chip works with digital logic. Compared to transistor-based fuzz circuits, there is no “in-between”, no “dynamic range”, and no “vintage tone”. There are just 1’s and 0s’.

So, no matter which kind of waveshape you put into it, the output will always be square. This is because a square wave is as distorted as a guitar signal can get.

The URLA obviously makes no exceptions. It provides an overdriven, brutal, glitchy and gated fuzz sound with a decay that dies abruptly. It still allows each note to be sustained. This is thanks to a bass boost stage at the very beginning of the signal path.

Dual Resonant Filter

This is the second effect in the internal signal chain of the Urla. It consists of a faithful replica of the analogue filter section of the  Korg MS-20. It is our all-time favorite vintage monophonic synthesizer.

It is a high pass filter in series with a low pass one. Both are 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.

Controls:

• Volume – Filter: Sets the output level of the dual filter.
• Blend: As the name suggests, this control allows mixes  the fuzz sound with the dry signal.
• Volume – Fuzz: Sets the output level of the fuzz.
• Cutoff – HP & LP: These knobs allow set the high pass (HP) and low pass (LP) frequencies. This makes the Urla super exciting and flexible. We placed those on the outside of the pedal  because you’ll love exploring the wild excursions sounds that can be produced. . In fact, depending on the place of their relative Peal knobs, they can go approximately from 0hz (so you’ll mute your signal completely when at least one of their respective knobs are fully closed) to 15kHz.
• Peak – HP & LP: While the high and low pass filters remove harmonics, their respective resonances creating a secondary peak that affects and colours the original signal.
  Use the knobs carefully! Depending on how the cutoff knobs are set, they can really make your amp scream, and/or boost low ends massively when set at high levels!
• For that reason, we highly recommend keeping the filter volume as low as possible when starting to adjust this effect.
• Expression: We’re not going to lie! If you dont use an expression pedal (by using a TRS cable) to control the cutoff, you’ll probably miss more than the 90% of the fun.
  For that reason, our friend Luca Romanelli (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.

The Urla is aggressive!

As aggressive as it is experiment-friendly, the Urla is AC Noises tribute to all the industrial, noise and alternative artists/records that made our world a better place to live.

Switching System: true bypass managed by soft switch + programmed relay.

Power: 9v center negative. Current draw: 100 mA minimum