Thirty-six knobs, six inputs, six outputs, and a stereo matrix that just works.
Overview
The ADDAC814 6x6 Stereo Matrix Mixer is not subtle. It's a pair of Eurorack modules - ADDAC814A (jacks) and ADDAC814B (master controls) - that together form a full 6-in by 6-out stereo matrix, taking up 33hp of rack space. Patch it in and you get a routing hub, a feedback playground, and a CV switchboard all at once. It's the kind of module that makes you rearrange your whole system to give it room. Despite the density, owners report it feels intuitive - "very straightforward and stereo," as one reviewer put it.
The ADDAC814 is DC coupled, so it handles control voltages as easily as audio signals. You can route LFOs through the matrix just as cleanly as you'd send a drum bus to six different reverb returns. The jumpers on the back of both modules let you set each channel independently to Line or Synth Level. That tells you up front whether your outboard gear will clip or float. The left input channels are normalled to the right, so stereo pairing is automatic unless you override it. That saves cables without costing flexibility.
This module wants you to write on it. Blank spaces on the left and bottom edges of the panel are open for a Sharpie, so you can label your most-used sources and destinations. The 36 color-coded knobs are black for outputs A, C, E; dark red for B, D, F; and cream along the diagonal (1A, 2B, etc.) to mark potential feedback paths. That makes it easy to find 4D in a flash mid-performance.
Specifications
| Manufacturer | ADDAC System |
| Width | 25hp + 8hp (33hp total) |
| Depth | 45mm |
| Power | +12V 140mA / -12V 140mA |
| Current Draw | 140 mA +12V, 140 mA -12V, 0 mA 5V |
| I/O configuration | 6-in x 6-out stereo matrix mixer |
| Number of inputs | 6 |
| Number of outputs | 6 |
Key Features
Color-coded for clarity, not just flair
The 36 knobs solve a real problem: visual overload. In a dense matrix, it's easy to twist the wrong knob and send a snare into a feedback loop you didn't mean to trigger. The color scheme - black for A/C/E outputs, dark red for B/D/F, and cream for the diagonal - works as an instant map. The cream knobs (1A, 2B, 3C, etc.) point out the self-feedback paths, which are often the most musically interesting.
Expandable by design
The base 6x6 setup can grow. With additional modules like the ADDAC814A and ADDAC814C, you can expand to configurations like 12x6, 6x12, or even 12x12. All necessary ribbon cables are included for up to 12x12 setups, so there's no hunting for obscure connectors. The internal 34-wire ribbon cable linking the input and control modules is sturdy, and the jacks (on the 8hp module) are separate from the knobs (on the 25hp), which keeps the panel uncluttered.
DC coupled and level-flexible
Being DC coupled means the ADDAC814 passes anything, not only audio. Envelope generators, sequencer voltages, random sources - they all move through the matrix with the same clarity as a sine wave. Jumpers on the back switch each channel between Line and Synth Level. Bringing in a line-level drum machine? Set those channels to Line. Running purely modular CVs? Set them to Synth. That makes the module at home in hybrid systems as well as pure Eurorack rigs.
Historical Context
The ADDAC814 landed in a crowded week. Two other companies, After Later Audio with the Keanu and Toppobrillo with the MatrixPlexer, released new matrix mixers at the same time. In that context it was called "probably the most classic among the three new releases." While others leaned into digital control or touch interfaces, ADDAC stuck with analog pots and a physical layout that prioritizes clarity over novelty.
Collectibility & Value
The ADDAC814 is currently available as of May 2025, both as a fully assembled module and as a DIY kit. The 6x6 configuration (jacks + controls) as a kit costs €260 (excl. VAT), while assembled units have carried an original price of $379.99 or €389. Current market listings vary: Reverb lists it at $430.63, while other affiliate links show prices from $316 to over $400, so no single resale value has settled yet. It's not a rare grail, but owners seem to hold onto it. The average rating is Ø 4.00 from two votes, with feedback like: "I like the ADDAC very much because it is very straightforward and stereo."
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