For decades, modular synthesists have been pushing the boundaries of electronic music, but Portuguese manufacturer ADDAC System is now inviting players to reach beyond knobs, patch cables and sequencers and get their hands on something far more tactile, actual strings.
The company’s newly announced Four Strings Series represents one of the more intriguing developments in Eurorack synthesis in recent years, blending the physicality of stringed instruments with the flexibility of modular electronics. Designed as an open-ended performance platform rather than a conventional instrument, the system encourages musicians to explore entirely new approaches to sound creation, composition and live performance.
At its heart, the Four Strings Series began with a simple idea: what if a lap steel guitar or dulcimer could become part of a Eurorack system?
The challenge was creating a string-based instrument that could comfortably coexist with other modules inside a standard Eurorack environment. ADDAC’s solution was to develop a custom headstock and bridge arrangement that suspends four strings above the rack, leaving room beneath for a range of dedicated modules and performance tools.
From there, the project rapidly evolved into a comprehensive ecosystem of modules that transform strings into controllable sound sources capable of interacting with both human performers and automated electronic systems.
Below is a brief description of the different elements that make up the Four Strings Series:
ADDAC120 Headstock & Bridge
This is the base of the String modules, a Headstock & Bridge modules, allowing string gauges up to 0.055. Users can also make these holes larger to fit heavier strings. Both panels are 2mm stainless steel for strength. The headstock features 4 locking tuners for easier string installation. The ADDAC120 Headstock & Bridge is priced at €210,00.
ADDAC121 Humbucker
This is the simple Humbucker pickup module. It features Tone and Volume controls as well as a LOW/HIGH gain switch for saturation. An integrated pre-amplifier brings the volume up to synth level. The height of the pickup can be adjusted using the mounting screws. The pickup can also be removed and used by hand. The ADDAC121 Humbucker is priced at €110,00.
ADDAC122 Quadraphonic Pickup
This is the Quadraphonic pickup, four independent pickups each with their own pre-amplifier, independent Volume control and output jack. A Mono Mix output (post volumes) is also available. All outputs are synth level. The height of the pickup can be adjusted using the mounting screws. The ADDAC122 Quad Pickup is priced at €290,00.
ADDAC124 Plectrums
This is the Plectrum module, featuring a servo per string allowing to pluck each string independently either from their dedicated push-buttons, incoming triggers or via MIDI. In Pluck mode the servo will move about 20 degrees efectivelly plucking the string. In Harmonic Mode the servo only moves about 10 degrees stopping at vertical position to lightly tap the string so that harmonics can be heard. The ADDAC124 Plectrums is priced at €280,00.
ADDAC125 Strings Mute
This module is inspired by Fender’s Mute system found in some Jaguar and Bass VI guitars where a piece of foam can be engaged to press against the string dampening their natural vibration. For this module we use a servo motor that raises and lowers a piece of foam that when pressed against the strings lightly dampens their natural vibration. While not as effective as a standard palm mute it allows a different tone to be automated. The ADDAC125 Strings Mute is priced at €45,00.
ADDAC126 Rotary Exciter
This module features a 7000 RPM brushless motor that rotates a surface with 4 magnets with opposed magnetic poles inducing a rotating magnetic field that will force the strings to vibrate whenever the rotational speed matches the frequency or harmonics of any of the strings tuning. The ADDAC126 Rotary Exciter is priced at €85,00.
ADDAC127 Ebow Slider
This module creates a harness and a sliding mechanism for a standard ebow. It allows the user to slide the ebow back and fourth below the strings. The ebow used features the “PianoBow” modification (https://ebow.com/diy-mods) where we sand off the Ebow’s feet so that it can get closer and avoid touching the strings when sliding it back and fourth. The height of the ebow can be raised or lowered using the four thumb screws. The ADDAC127 Ebow Slider is priced at €140,00.
Bow Arch Attachment
This attachment raises the two middle strings allowing a bow to reach each string individually.
Small Resonators
Although quite simple these are extremely efective adding harmonics to non-wounded strings. For every resonator attached to the string a new partial is added, placing more pieces adds more partials which makes the tone increasingly complex. The tuning of each harmonic is defined by the position of the resonator on the string – the resulting sound can be quite surprising as very much resembles a bell type sound.
ADDAC120F Strings Frame
This is a custom-built frame designed specifically for the ADDAC12X String modules. The Strings Frame is priced at €360,00.
• 90-240V AC Plug with fuse drawer (2 fuses: 1 installed, 1 spare)
• 122HP
• +12V 1.5A
• -12V 1.5A
• +5V 0.5A (from +12V)
All of the products within the Four Strings Series is available now – join the ‘string revolution’ in Eurorack synthesis. For more information, including each of the separate modules, frame, specifications and signal flow diagrams, please visit the ADDAC System website.
Australian distributor Found Sound: https://foundsound.com.au/
The Four Strings Series begins shipping in July, with modules available individually or as part of a complete system. For adventurous synthesists looking to venture into uncharted territory, ADDAC’s “string revolution” may be one of the most fascinating Eurorack developments of the year.