4-string Eurorack synthesizer with humbucker pickups - 197HP chassis
ADDAC120MHS is the Strings Humbucker system by ADDAC System, the most comprehensive configuration in the ADDAC modular string instrument ecosystem for Eurorack. Housed in a 197HP case, it integrates a headstock and bridge, humbucker pickups, robotic picks, automated muting, and a rotary exciter, offering a fully playable stringed instrument that can be processed and controlled via CV, trigger, or MIDI—ready to use in your modular system.
The ADDAC120 forms the physical foundation of the system—a Headstock & Bridge module that accommodates strings with gauges up to .055. The strings are installed exactly as on a guitar: the user is free to choose their preferred set of strings and tuning. The headstock is equipped with 4 locking tuners to make string installation faster and easier; the string holes can also be enlarged to accommodate thicker strings.
The set includes a Bow Arch Attachment, which raises the two center strings so that a bow can reach each string individually, and Small Resonators, which are simple yet extremely effective at adding harmonics to the unwound strings. Each resonator applied generates a new partial: by adding more, the timbre becomes progressively more complex, resulting in sounds reminiscent of a bell.
The ADDAC121 is the system’s humbucker pickup module, equipped with Tone and Volume controls and a LOW/HIGH gain switch to add saturation to the signal. A built-in preamp boosts the volume to synth levels. The pickup’s height is adjustable via the mounting screws, and it can also be removed for manual use.
The ADDAC124 features a servo motor for each string, allowing you to pluck them independently via dedicated buttons, input triggers, or MIDI. In Pluck mode, the servo moves approximately 20 degrees for a full pluck; in Harmonic mode, the movement is reduced to about 10 degrees, lightly touching the string to bring out the harmonics—by positioning the module at the midpoint, 2/3, or 3/4 of the string’s length. Up to 3 modules can be daisy-chained to pluck and generate multiple harmonics simultaneously. Twelve replacement picks are included.
Four 3-position switches allow you to control the module’s behavior: the top position disables the trigger and MIDI, leaving only the buttons active; the middle position activates Pluck mode with all inputs active; the bottom position activates Harmonic mode, also with all inputs active. The height of the picks is adjustable via screws—lower for Pluck mode and raised by about 4 mm for Harmonic mode.
Inspired by the mute system found on some Fender Jaguar and Bass VI guitars, the ADDAC125 uses a servo motor to raise and lower a sponge that, when pressed against the strings, slightly dampens their natural vibration, producing a tone different from that of a traditional palm mute. The module is passive and must be connected to an ADDAC124 Plectrums, either by replacing one of its servos or by operating in parallel using the included splitter cable. For maximum effectiveness, position it as close to the headstock as possible.
The Rotary Exciter features a 7,000 RPM brushless motor that rotates a surface equipped with four magnets of opposite polarity, generating a rotating magnetic field. When the rotation speed matches the fundamental frequency or harmonics of a string, the string is forced to vibrate, creating sonic textures that would otherwise be impossible to achieve manually. A Speed knob and a CV input allow for nonlinear control of the motor speed.
Technical Specifications
€ 1.220,00 Ex VAT
For European customers, select your country to view the correct price including VAT.
Normally delivered in 10-15 working days
Empty cart
