ADDAC 814 6x6 Stereo Matrix Mixer (2024–)
A tangle of patch cables leads to a moment of pure sonic alchemy—this is where chaos learns to sing in stereo.
Overview
Picture a modular patch with a feedback loop running through three filters and a delay. The mixer can't handle the cross-connections without a nest of spaghetti. The ADDAC 814 6x6 Stereo Matrix Mixer is built for exactly that job. Every one of six stereo inputs can go to every output at once. The wall of 36 knobs looks like overkill, especially in a format where every HP counts. The clever part is the split into two modules, one for controls and one for jacks. The cable jungle goes off to the side and the performance surface stays clean.
It also expands. Need 12x12? Chain two together. Want a 24x24 for a studio centerpiece? ADDAC supports it, with expansion headers and full documentation on how to scale up. Even standalone, the 6x6 offers more routing than most modular users will fully exploit. It's DC-coupled, so it handles both audio and CV. That makes it as useful for modulation matrices as for blending oscillators or effects returns. The left inputs are normalled to the right, which simplifies stereo operation. Patch the right side independently if you want true dual-mono or cross-panning. The knobs come in black, dark red, and cream. The cream ones form the diagonal (1A, 2B, 3C, etc.), which hints at feedback paths. The alternating black and red help you track output columns at a glance.
This is not a "set and forget" module. It's tactile and wants your hands on it. Turn one knob and you reshape everything downstream. Feedback loops build, modulations evolve, and stereo images shift in real time. It has quirks, too. The knobs are trimmer toppers (Thonk's Tall Trimmer Toppers), so fingers need some precision. Some users report they'd prefer full-sized knobs for live use. ADDAC clearly prioritized space and density, and at 33HP that makes sense. The pots are Alpha T18s with metal shafts, so they'll last. Replacing all 36 with larger knobs is a project in itself.
Specifications
| Manufacturer | ADDAC System |
| Production Years | 2024– |
| Original Price | 340€ (Control + Jacks modules) |
| Format | Eurorack |
| HP | 25HP + 8HP (33HP total) |
| Depth | 4.5 cm |
| Current Draw +12V | 140mA |
| Current Draw -12V | 140mA |
| Inputs | 6 stereo inputs (12 total jacks) |
| Outputs | 6 stereo outputs (12 total jacks) |
| Input Normalization | Left inputs normalled to right per channel |
| Signal Type | DC coupled (audio and CV capable) |
| Level Switching | Per-channel jumper selectable (Eurorack or Line level) |
| Internal Connection | 34-wire ribbon cable between control and jack modules |
| Expandability | Supports chaining for 6x12, 12x6, 12x12, 18x18, etc. |
| Expansion Headers | Extra IDC sockets for linking multiple units |
| Potentiometers | Alpha T18 with metal shafts, fitted with Thonk Tall Trimmer Toppers |
| Panel Features | Scribble strips for labeling inputs and outputs |
| Knob Colors | Black (A, C, E outputs), Dark Red (B, D, F outputs), Cream (diagonal feedback path) |
| Module Components | Control Module, Jacks Module, optional Expansion Module |
Key Features
A Split-Personality Design That Solves the Cable Chaos
Most matrix mixers put all the jacks and knobs on a single panel, and the cables end up covering the controls. The ADDAC 814 splits into two modules instead: the 25HP control unit with all 36 knobs, and the 8HP jack module with all 24 input/output jacks. They connect via a 34-wire ribbon cable. You can mount the jack module off to the side, below, or even in a different row. During live sets, the control panel stays clear while all the cabling goes to a dedicated zone. Servicing is easier too, since you don't unplug half your system to reach a buried jack. Only the control module needs bus power, so the jack module installs anywhere. You can also put it in a skiff or secondary row and save front-panel space.
Expandable to Monstrous Proportions
The 814 is a building block. With extra IDC headers on the back, you can chain multiple units into larger matrices: 6x12, 12x6, 12x12, even 18x18. ADDAC provides cabling for configurations up to 12x12. Beyond that, custom cables are required, but the company offers guidance and discounts for large builds (7% off orders over 18x18). Start with a single 6x6 for stereo effects routing, then expand as your system grows. A 12x12 matrix can handle entire synth layers, live processing chains, or serve as a central hub for a multi-rack setup. You can also mix and match configurations, like using one control module with multiple jack modules.
Designed for Both Audio and CV Mastery
Many mixers are audio-only. The 814's DC-coupled circuitry lets it handle control voltages as well as audio. You can blend LFOs, morph between envelope shapes, or build evolving CV textures by feeding outputs back into inputs. Patch a few slow LFOs into the top channels, route them through various feedback paths, and use the matrix to crossfade between modulation states. The level jumpers (per-channel, on the back) switch between Eurorack and line level. That makes it easy to bring in external gear like guitar pedals, outboard effects, or audio interfaces. It works as an audio router and a CV processor.
Historical Context
Matrix mixers have always been niche in modular synthesis because they demand a different way of thinking. Traditional mixers follow a linear path: input → channel → output. Matrix mixers allow any input to go to any output, with level control at every intersection. In the early days of Eurorack, space and cost limited their adoption. By the mid-2020s, systems had grown larger and users wanted more complex routing, and demand for flexible mixers surged. The ADDAC 814 arrived in 2024 as part of this wave, joining a small but growing field that included the AI Synthesis 018, Bear Audio Matrix, and SetonixSynth Shaka. What set the 814 apart was its expandability and split design, which addressed usability issues others had overlooked. Many manufacturers were shrinking modules to save space. ADDAC went big, betting that users would value power and flexibility over footprint.
Collectibility & Value
As a 2024 release, the ADDAC 814 is too new to be considered "vintage" in the traditional sense, but its design and expandability have already made it a sought-after centerpiece in serious Eurorack rigs. New units sell for around €340 directly from ADDAC, with the jack and control modules available separately (€80 and €260 respectively) for custom builds. On the secondhand market, complete units list between $350 and $450, depending on condition and included accessories. The DIY kit option (€260 for the full 6x6) keeps costs down, though assembly requires intermediate soldering skills and patience. 36 pots and dense wiring aren't for beginners. Failures are rare, but check the ribbon cable connection if the module behaves erratically. Loose connections here can cause intermittent signal loss. The Alpha pots are robust, but the trimmer-topper knobs can be fiddly. Some users replace them with larger knobs, though that isn't trivial given the tight spacing. When buying used, verify that all jacks are secure and that the level jumpers function correctly, especially if integrating with line-level gear. The skiff-friendly depth (4.5cm) and solid build make it reliable for touring, but its size means it's best suited for larger systems.
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