ADDAC 807B (2017–2023)

A compact Eurorack module that turns a modular into a mixing console, with CV control, level controls and some vintage warmth.

Overview

The 807B is 24 HP wide and not a bare-bones summing module. The front panel is clean, labeled well, and has just enough color coding to keep you from patching the wrong jack. The 807B is the "Inputs Console" half of the larger ADDAC 807 system and is meant to pair with the 807A for full stereo mixing. Plenty of users run it standalone as a high-fidelity entry point for external gear. It takes signals from a drum machine, a guitar, a field recorder or a vintage synth, then converts, attenuates, amplifies and hands them off to the rack.

Eurorack voltage standards can be a minefield, and the 807B sorts them out. Line-level, instrument-level and mic-level signals get normalized to modular-friendly voltages, so a Korg MS-20 doesn't clip and an acoustic guitar doesn't vanish into hiss. It has five stereo input channels, each with its own level control and CV attenuation, so you can automate input gain from inside the system. Most external mixers can't do that without a pile of extra modules. There's also a matrix routing section that sends any input to any output bus, which comes in handy in a live set when you need to reroute a feedback loop on the fly.

Compared to a basic audio interface or a standalone mixer, the 807B keeps everything in the modular ecosystem. No breakout cables across the floor, no latency, no level mismatches. It has no EQ and no effects loops. Those are handled in the 807A or with other modules. It is clean and transparent, with a subtle warmth. Some users report a slight "vintage" character, not in the overdriven sense, but in the way it smooths transients just enough to feel musical rather than clinical.

Specifications

Key Features

CV-Controlled Input Level Automation

Each of the five stereo channels has a dedicated CV input with a manual attenuverter. You can modulate input gain from an LFO, envelope, sequencer or even another audio source. A field recording can swell as a slow sine wave modulates its level, or a guitar signal can duck every time a kick drum hits, all without leaving the rack. This is mix automation built into the input stage, which is rare in Eurorack and removes the need for a separate VCA on every external source. The attenuverter scales the CV response from subtle nudges to full tremolo, and since the control voltage is DC-coupled, it handles both audio and CV signals.

Intelligent Level Conversion

Each input channel has selectable level conversion modes: line-to-modular, instrument-to-modular and mic-to-modular. You can plug in a bass guitar, a TR-808 and a condenser mic at once, and the 807B handles the translation so none of them overload or get lost. The mic preamps are clean and quiet, with switchable 48V phantom power, which makes direct vocal or acoustic instrument recording into modular workable. Some users treat the 807B as the "front door" of their system: everything comes in here, gets normalized, then gets distributed.

Matrix Routing for Dynamic Signal Flow

Behind the row of knobs is a routing matrix that assigns any input channel to any of the stereo buses. You could send a drum machine to Bus A, a guitar to Bus B and a field recorder to both, then route Bus A to the 807A for the main mix and Bus B to a delay module. You could also build submixes that feed different parts of a patch. The matrix is switched manually with front-panel toggles, so it is not CV-controllable. That keeps it simple and immediate in live performance, with no menu diving and no app.

Historical Context

The ADDAC 807 system launched in the late 2010s, when Eurorack was deep into its expansion but integration with the outside world was still clunky. Most racks relied on a patchwork of audio interfaces, standalone mixers and breakout boxes. The 807B, along with the 807A, was one of the first modules to treat external signal integration as a core function. It arrived alongside similar efforts from WMD (Performance Mixer) and Intellijel (Mixup). Where others focused on in-rack mixing, ADDAC built a console.

Portugal-based ADDAC System had already earned respect for thoughtful, musician-first designs, and the 807 series cemented that. ADDAC focused on real-world problems: level mismatches, lack of automation, and the hassle of patching in external gear. The 807B borrows concepts from analog mixing consoles and translates them into modular terms. Competitors like the A&H MixWizard 4 offered physical faders and EQ but lacked CV integration. The 807B is the reverse: no EQ, but full automation and routing flexibility.

Collectibility & Value

The 807B is not a rare bird, but it's not common either. It was produced from 2017 to 2023 and saw steady demand without flooding the market. As of 2026, used units trade between €250 and €350, depending on condition and whether they're sold with the matching 807A. Units in excellent condition with no blemishes or loose jacks command the higher end, especially with the original packaging or documentation. There are no known fatal flaws, but service technicians observe that the 3.5mm jacks can loosen over time with frequent plugging and unplugging, especially with stiff or heavy cables. A full recapping isn't typically needed. Owners report that cleaning the input jacks and checking solder joints every few years keeps performance optimal.

Before buying, test every input channel with a known signal source and listen for crackling, imbalance or dropouts. Verify that the CV attenuverters respond smoothly across their range. Confirm that phantom power (if used) engages cleanly and doesn't introduce hum. Some early units had minor firmware quirks in the matrix routing logic. These were resolved in later production runs, so later serial numbers are preferred. The 807B is often sold paired with the 807A, so buyers should ensure both modules are from the same era. There were minor spec changes between revisions, and mismatched units can have level inconsistencies.

It's not a "grail" module. Collectors don't hoard it for resale but for utility, and once a system is built around it, replacing it means rethinking the entire signal flow.

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