ADDAC System 814

A Eurorack matrix mixer for patching that would otherwise be a mess - if you have the rack space to spare

Overview

The ADDAC System 814 6x6 Stereo Matrix Mixer is part of the ADDAC800 Series (Analog Sound Utilities). It doesn't just blend signals. It lets them cross over, route, reroute and interact, which feels more like conducting than mixing. It isn't flashy, but it is well thought out, and it reveals itself over weeks of use. It's a Eurorack puzzle box for people who like solving audio problems on the fly.

The 814 is a 6x6 matrix: six inputs, six outputs, each intersecting at a dedicated attenuverter. Instead of linear channels, it's a grid where every input can be scaled and routed to every output. One LFO can modulate multiple VCOs with independent levels. Six different drum voices can be dynamically panned across six effects returns. Because it's DC coupled, it handles both audio and CV, which opens up a lot of room in patch design.

It demands respect. Owners report that subtle tweaks are the best course of action, as things can get wild fast. One small turn too far, and a delicate ambient pad becomes a feedback storm. Once you get your head around the concept, the 814 is a joy to use, offering interesting opportunities for patching and the ability to grow with your rig. It's not a module you throw in for convenience. You plan for it, both sonically and physically.

Specifications

Manufacturer	ADDAC System
Model	814 6x6 Stereo Matrix Mixer
Product type	Eurorack module, Stereo matrix mixer
Series	ADDAC800 Series (Analog Sound Utilities)
Size	33HP total (25HP control section + 8HP jack section)
Depth	4.5cm
Power consumption	140mA +12V, 140mA -12V
Signal compatibility	DC coupled (works for audio and CV)
Configuration	6x6 Stereo Matrix
Channel normalling	The left side of each channel is normalled to the right

Key Features

Matrix-Based Signal Routing

There are no faders or channel strips here. The 814 is built around a matrix topology, so every input has a dedicated attenuverter for every output. That's 36 points of control in total, each knob setting how much of input A reaches output 1, B reaches 3, and so on. You can use it to crossfade between textures, create complex modulation matrices, or build feedback loops that evolve over time. It's simple to navigate and use, but it can generate complex results.

Flexible Level Switching

On the underside of the module, small switches let you toggle each channel between synth level and line level. Bringing in a drum machine or external synth at line level? Flip the switch. Keeping it all within Eurorack? Stick to synth level. Being able to swap levels on the fly means the 814 can sit at the center of a hybrid setup.

Scribble Strips for Patch Clarity

Each input and output has a scribble strip, a small label area you can write on with a pencil. Patch memory is fleeting in a modular system, so this is handy. In a complex patch, you can label things like "Bass Drone," "Reverb Send," or "LFO Mod."

Modular Physical Design

The 814 comes in two physical sections: a 25HP control panel with all the knobs and switches, and an 8HP jack panel that houses the inputs and outputs. They connect on the rear via ribbon cables, which keeps the front-panel layout clean and the patch points accessible. The split also makes it easier to mount in tight cases, though the total footprint of 33HP is undeniably large. Reviewers note the footprint as a trade-off, but the layout is easy to read and adjust, especially in live performance. There are also extra sockets on the back for expanding into multi-matrix setups, so you can daisy-chain multiple 814s into a larger routing network.

Build Quality and Confidence

Build quality is excellent - solid and tight. The knobs have a firm, precise feel, the panel is thick and well finished, and the internal construction feels built to last. Flimsy modules can wobble in their slots, but the 814 doesn't. Every detail, from the ribbon cable connection to the placement of the level switches, feels considered.

Collectibility & Value

As of February 2026, the ADDAC System 814 was priced at £340 in new condition, according to available reviews. This reflects its contemporary market value rather than an original retail price, which has not been confirmed. Given its niche but growing reputation among modular users, and the lack of widespread production data, it's likely that the 814 remains a low-volume, specialist module rather than a mass-market staple. No information is available about common failures or maintenance issues. Collectibility is currently driven more by utility than nostalgia. Active modular users seek it out, not vintage hunters.