ADDAC 300A (2022–)
A small module that starves other modules of voltage until they glitch, go unstable and break up. It works like a controlled power failure with knobs on.
Overview
The ADDAC 300A is a module built to make other modules fail, and it does that in a controlled way. It isn't meant to blow anything up, though you should still be careful. It pushes your gear to the edge of collapse, where the interesting artifacts live. The 300A is part of ADDAC's 300 Series, a line focused on power manipulation and circuit-level mischief. It's built for the Eurorack experimenter who has already tried every filter, every LFO and every modulation source, and now wants to know what happens if the module is underfed.
The 300A is a dual power starvation module. It lets you independently reduce the positive and negative voltage rails going to two separate Eurorack modules. You plug your target module into the 300A with IDC cables (standard Doepfer-style), then use the front-panel potentiometers to dial down the voltage it receives. Most analog modules expect ±12V or ±15V. Drop that to ±5V or lower and strange things happen: filters warp unpredictably, oscillators sputter and fold back, delays glitch and stutter, and mixers distort in organic, non-linear ways. Think of it as a hunger strike for your synth.
ADDAC did more than slap together a voltage dropper. The 300A has trimmers on the back to set a minimum voltage plateau, so you don't accidentally drop to 0V and kill your module. That matters because some circuits tolerate deep voltage reduction, while others shut down or misbehave below certain thresholds (usually between 3V and 10V, depending on design). The trimmers let you define a safe floor, and the front pots sweep through the usable range above it. Each channel also has a bypass switch, so you can A/B the effect instantly. Build quality is solid, with clean silkscreen, sturdy knobs and a compact 4 HP width.
It is risky. Power starvation isn't a "set and forget" effect, and it can stress components, especially in modules not designed for it. The 300A is explicitly not recommended for modules drawing more than 75mA per rail, and ADDAC warns users to proceed at their own risk. This is gear for tinkerers. Anyone who has bent a circuit or modded a pedal will know the idea.
Specifications
| Manufacturer | ADDAC System |
| Production Years | 2022– |
| Original Price | €70 |
| Width | 4 HP |
| Depth | 40 mm |
| Max Current Draw | 20 mA |
| Bus Board Connector | 8-pin and 10-pin IDC (Doepfer style) |
| Module Power Rails | ±12V or ±15V input |
| Output Voltage Range | Adjustable down to user-set minimum (via rear trimmers) |
| Supported Module Consumption | Up to 75 mA per rail |
| Channels | 2 independent |
| Bypass Switches | Yes, per channel |
| Rear Trimmers | Yes, for setting minimum voltage plateau |
| Weight | Approx. 100 g |
| Country of Manufacture | Portugal |
Key Features
Controlled Voltage Collapse
Most power starvation hacks involve physical mods, resistors or risky jumper wires. The 300A brings the technique into the modular workflow, and makes it patchable, reversible and repeatable. You can set a sweet spot where your analog delay starts to warble but doesn't drop out, or where a filter oscillates in a new, unstable way. Because the effect is applied at the power level, it reaches every part of the circuit, not just the audio path. So it changes the module's behavior as well as its sound. An LFO might slow down erratically, a VCA might gate unpredictably, a sequencer might skip steps.
Dual Independent Channels
Two channels mean you can try different voltage profiles on two modules at once. You might gently starve a filter while completely crippling a reverb. Or you might run two oscillators at different voltages to get beating, detuned textures that shift over time. The channels are completely independent, each with its own bypass and voltage control, so the treatments don't have to match. The module draws only 20 mA from the bus, which leaves headroom for the modules it's feeding (or starving).
Trimmer-Set Floor for Safety
The rear-mounted trimmers set a minimum voltage. This stops the front-panel pots from going too low and potentially damaging sensitive circuits. You can calibrate each channel to cut off before reaching dangerous levels, say 4V or 5V, then use the knobs to sweep from that floor up to full voltage. It's still up to the user to know their modules. Some digital modules, for example, will hard-reset or lock up if voltage drops too far. The 300A works best with analog circuits such as filters, oscillators, VCAs and mixers, where voltage fluctuations create musically useful artifacts rather than system crashes.
Historical Context
Power starvation as a sonic technique predates modular synthesis. It's a staple of circuit bending, where DIY enthusiasts underpower low-voltage devices like kids' toys or drum machines to get glitchy, unpredictable sounds. The practice became popular in the 1990s and 2000s among noise and experimental musicians, but it was always a physical hack, not a patchable effect. ADDAC's 300 Series brought it into Eurorack without soldering irons or multimeters. The 300A, along with its sibling the 300 (which covers higher-current modules), was part of a wave of modules focused on power manipulation.
ADDAC System is based in Lisbon and has built a reputation for modules that bridge vintage inspiration with modern utility. The 300A doesn't emulate a classic piece of gear. While competitors focused on digital effects or complex sequencers, ADDAC concentrated on modules that interact with power, light and touch in unpredictable ways. The 300A is a niche product.
Collectibility & Value
The ADDAC 300A isn't a collector's item in the traditional sense. It's too new, too utilitarian and too specialized. But it has a loyal following among experimental modular users, and used units hold their value well. New, it retails for around €70, and used examples typically sell for €50 - €65 depending on condition and market availability. It isn't rare, but it isn't mass-market either. Production is steady but limited, and it doesn't flood the used market like more mainstream modules.
Failures are uncommon. The most important thing to check when buying used is the integrity of the IDC connectors on the back. These are the points where your modules physically plug in, and repeated insertion and removal can wear them out or loosen solder joints. A wobbly connection here could mean intermittent power or, worse, shorting. Also verify that the trimmers work. Some users set them and forget them, but if they're seized or damaged, you lose the safety floor. The module has no moving parts besides the pots and switches, so mechanical wear is minimal. There is no firmware and no software.
It isn't a daily-driver effect. It's a color tool and a glitch source, a way to break your rig in creative ways. It pairs especially well with analog delays, resonant filters and chaotic sequencers. If your system is mostly digital or you want clean, polished sounds, the 300A might sit unused.
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