ADDAC 306 Touch Controller (2019–)
A five-channel voltage controller that moves several parameters with one slider
Overview
It doesn't make a sound, but the ADDAC 306 Touch Controller does a lot in the right patch. The slider sweeps five independent CV channels at once. You set the start and end points for each channel, define their range and direction, then glide from one state to another. Freeze a patch in "state A," build a different one in "state B," and move the slider to go from one to the other.
Originally introduced as the ADDAC 306 VC Transitions, this module is a hands-on macro controller that doesn't rely on presets or digital recall. Each of the five channels has MINIMUM, SPAN, and DIRECTION controls. No menus, just knobs and switches. The MINIMUM sets the baseline voltage, SPAN determines how far above that baseline the output can climb, and DIRECTION flips whether the transition moves up or down as the slider advances. That gives you five independent CV curves, all slaved to a single physical gesture. One parameter can rise while another falls, and a third can jump abruptly halfway through.
And while it’s billed as a “touch controller,” don’t expect capacitive pads or ribbon strips—the “touch” here is literal: you touch the slider. It’s a sturdy horizontal fader, not the tiniest component on the panel, but not huge either. Some users report it feels a bit cramped in dense racks, especially when trying to make subtle adjustments mid-performance. But that’s part of its charm: it demands engagement. You’re not just setting and forgetting; you’re performing. The module also accepts a CV input, so you can replace manual control with an LFO, sequencer, or envelope, turning the slider into an attenuverter for the incoming signal. This turns one ADDAC 306 into a modulation multiplier—patch an ADSR into the CV IN and suddenly you’ve got five differently shaped envelopes derived from a single source.
Specifications
| Manufacturer | ADDAC System |
| Production Years | 2019– |
| Original Price | €113.90 (kit), ~$235 (assembled) |
| Format | Eurorack |
| Width | 8 HP |
| Depth | 40 mm |
| Power Consumption +12V | 50 mA |
| Power Consumption -12V | 50 mA |
| CV Outputs | 5 channels |
| Output Voltage Range | 0–5V or 0–10V (jumper selectable per channel) |
| Max Current per Output | +40mA / -20mA |
| CV Input | 1 (attenuated by slider position) |
| Transition Control | Manual slider + CV control |
| Channel Controls | MINIMUM, SPAN, DIRECTION (per channel) |
| Bus Board Connector | 8-pin IDC (Doepfer style) |
| Panel Material | Black anodized aluminum |
| Assembly Type | Available as DIY SMD/through-hole kit |
| Development Credit | Konstantine Fioretos (concept) |
Key Features
A Five-Channel Voltage Morph Engine
The 306 morphs between two defined voltage states. You don't program curves, you set them in real time. Set all five MINIMUMs to define "state A," then adjust the SPAN controls to define "state B." Slide the fader, and each output ramps or drops according to its DIRECTION switch. It isn't a sequencer or a random generator. It suits live performance, where you might want to shift an entire patch from "ambient drift" to "rhythmic chaos" with one hand. Musicians have used it to morph filter cutoffs, LFO rates, oscillator pitches, effect mix levels, and even sequencer gate lengths, all in sync, all tied to a single gesture.
CV Control with Manual Override
The CV input also makes the 306 a modulation multiplier. Patch in an LFO, and the slider becomes an attenuator, letting you manually scale how much of that LFO affects the transitions. Patch in a gate or trigger, and you can snap between states abruptly. You can automate the transitions during composition, then take manual control during performance. You can also use the CV input to slave multiple 306s together. Two modules give you ten channels under one slider; three give you fifteen. The limit is rack space and power.
Jumper-Selectable Output Range
Each channel's maximum voltage can be set via internal jumpers to either 5V or 10V. Some modules respond better to 0-5V (like many quantizers or digital oscillators), while others want 0-10V (like analog filters or VCAs), so the 306 lets you set each output independently. Few modules at this price point offer that. Grab a tiny screwdriver before firing up your soldering iron.
Historical Context
The ADDAC 306 arrived in 2019, when Eurorack was deep into "utility" modules, small focused tools that solved specific patching problems. The 306 wasn't a sound source or an effects processor. It was a meta-controller, part of a growing trend of modules that let users shape entire patches rather than individual parameters. It shared DNA with the Livestock Electronics Ellis, the FSS Makrow, and the Befaco Rampage, but stood out with its five-channel design and hands-on immediacy. Unlike the Makrow's single-knob simplicity or the Ellis's voltage-processor complexity, the 306 sits in between: simple enough to learn in minutes, deep enough to use for years.
It also reflects ADDAC's philosophy of hybrid instruments that blend analog control with digital precision. The 306 is fully analog in operation, though its design feels digital in intent. It was developed in collaboration with Konstantine Fioretos, a designer known for performance-oriented tools. There are no menus, no screens, and no patch memory, just voltage, knobs, and a slider.
Collectibility & Value
The ADDAC 306 isn't a vintage item in the traditional sense. Production began in 2019 and continues today. Its value holds well, especially for assembled units. The DIY kit retailed for around €114, while completed modules often sell for $200 - $250, depending on condition and seller. Used units in good working order typically go for $150 - $180.
Failures are rare, but a few things need watching. The slider can wear out with heavy use, so listen for crackling or dropouts when moving it slowly. The jumpers for voltage range are tiny and can be dislodged during shipping or installation, so verify output ranges if buying used. Since it was sold as a kit, some units may have been poorly assembled. Check for cold solder joints, especially on the power connector and output jacks. A multimeter test for shorts is wise before plugging into a powered system.
For collectors, the 306 isn’t about rarity or resale value—it’s about utility. It’s the kind of module that, once you’ve used it, you can’t imagine living without. It doesn’t age like a vintage synth; it integrates. And because it doesn’t make sound, it’s often overlooked in “must-have” lists—until you see it in action. Then it’s obvious: this is the hidden hand behind the magic.
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