ADDAC 300 Series (Announced 2014)
Wires, electrodes, and foot pedals - this is modular synthesis with your whole body, not just your hands.
Overview
The ADDAC 300 Series isn't about oscillators or filters. It's about control, and some of it is physical and a little odd. These Eurorack modules from ADDAC System were built to get away from knob-twiddling. They let you work a modular rig with muscles, pedals, and even power glitches. The series was announced in January 2014 and framed as a set of "new/diferent expression aproaches" and "new interfaces for analog synthesizers." Nothing here makes sound on its own. What you get are tools that make your existing modules respond in ways they weren't designed to. They connect the player's body to the machine, for performers who want to move beyond the keyboard-and-patch-cable paradigm.
At the core of the series are the ADDAC301 Floor Control and the ADDAC301B Dual Expression Attenuator, which bring pedal-based expression into Eurorack. Then there's the ADDAC303 Muscle Sensing, which reads muscle tension through electrodes and turns flexes into control voltages. The ADDAC300 Power Starvation is a circuit-bending idea in module form. It lets you underpower other modules to induce glitchy, unstable behavior. It's not flashy, but it's clever. These are utility modules, and they're all bright red. One forum user openly questioned that, wondering if they were the only one held back by the color.
Specifications
| Manufacturer | ADDAC System |
| Product type | Modular synthesizer/Eurorack modules, part of the "ADDAC300 Expressive Controls Series" |
| Model | ADDAC300 Power Starvation |
| Width | 4 HP |
| Depth | 4 cm |
| Max current | 5mA |
| Bus Board Cable | 8 × 2 IDC (Doepfer style) connector |
| Model | ADDAC301 Floor Control |
| Width | 4 HP |
| Depth | 4 cm |
| Max current | 20mA |
| Bus Board Cable | 8 × 2 IDC (Doepfer style) connector |
| Model | ADDAC301B Dual Expression Attenuator |
| Passive Module | Yes |
| Width | 4 HP |
| Depth | 3 cm |
| Model | ADDAC301C Dual Sustain Switcher |
| Passive Module | Yes |
| Width | 4 HP |
| Depth | 3 cm |
| Model | ADDAC303 Muscle Sensing |
| Width | 4 HP |
| Depth | 4 cm |
| Max current | 60mA |
| Bus Board Cable | 8 × 2 IDC (Doepfer style) connector |
Key Features
ADDAC300 Power Starvation: Starve It to Make It Sing
This module takes a staple of circuit bending, the deliberate underpowering of chips to create glitchy, unstable tones, and makes it modular. You plug another module through it, then use trimmers to adjust the ± power supply independently. You can even set a minimum voltage plateau so things don't collapse entirely. It's not destructive when used carefully, but it will push your gear into sonic territory it was never meant to explore. As ADDAC put it, the idea is rooted in the first hack any DIYer learns: power starvation. Now it fits in a 4 HP slot, with bypass switches so you can flip back to normal operation instantly. It draws only 5mA.
ADDAC301 Floor Control: Feet on the Controls
Your hands are busy patching or playing keys, but your feet are free. The ADDAC301 Floor Control lets you plug in standard expression and sustain pedals for real-time control over CV parameters. The Range knob sets the voltage swing from -10V to +10V. The Offset knob shifts that entire range up or down by ±5V. So you can map a pedal's motion where you need it, say from 2V to 5V for a filter sweep, or -3V to +3V for subtle pitch modulation. It also generates a gate signal from the sustain pedal, with an LED to confirm activity. A jumper adds a removable +5V adaptor, which makes it compatible with bus boards that need it. It draws 20mA and is 4 HP wide.
ADDAC301B & ADDAC301C: Passive Pedal Power
These two are siblings in function but opposites in behavior. The ADDAC301B is a passive dual expression attenuator. Plug any CV or audio signal through it, and an expression pedal controls its amplitude. The invert switch flips the pedal's response, so pushing forward lowers the level instead of raising it. It's 4 HP wide and only 3 cm deep. The ADDAC301C, also passive and 4 HP, does the same job but for on/off control via sustain pedals. Plug in an audio or CV source, hit the pedal, and you toggle the signal state. Neither needs power, so neither eats up current.
ADDAC303 Muscle Sensing: Your Biceps as a Synth Controller
This is the showstopper. The ADDAC303 uses electrodes to sense muscle tension and turns flexes into control voltages. It ships with electrodes. A Gain knob sets the output range (±10V), an Offset knob positions the baseline, and a Smooth switch chooses between hard or soft transitions. You get both positive and inverted CV outputs, plus a comparator gate output with its own Threshold knob, so you can trigger events when tension crosses a set level. One forum user responded to its announcement with "Mmmm, muscle sensing. Wire me up." It's 4 HP, 4 cm deep, and draws 60mA. That's hefty for a control module, but it makes sense given the onboard processing.
Historical Context
The ADDAC 300 Series emerged from a desire to expand how we interact with modular systems. As ADDAC System stated, these were "new interfaces for analog synthesizers," born from the observation that while hands are busy during performance, feet and bodies are often idle. The ADDAC301 Floor Control was explicitly conceived to solve that. The Power Starvation module taps into circuit-bending lore and brings a grassroots hacking technique into Eurorack. The Muscle Sensing module was positioned as a "totally new interaction principle for the eurorack format." All of these modules were part of the "ADDAC300 Expressive Controls Series."
Collectibility & Value
Original pricing as of January 2014 was: ADDAC300 Power Starvation at 70,00 €, ADDAC301 Floor Control at 70,00 €, ADDAC301B Dual Expression Attenuator at 65,00 €, ADDAC301C Dual Sustain Switcher at 60,00 €, and the ADDAC303 Muscle Sensing at a steep 180,00 €, reflecting its complexity. There is no data on current market prices, production end dates, or common failures. Maintenance and reliability concerns are unreported in the sources. Some users noted the bright red color as a hesitation point, though others found the modules "very handy" and praised ADDAC as a company to deal with.
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