ADDAC 200S (2023–)

A tiny, passive Eurorack hero that solves a daily patching headache—no power, no fuss, just clean 1/4" to 1/8" conversion right on your panel.

Overview

You know that moment when you're knee-deep in a patch, cables snaking everywhere, and you suddenly realize you need to plug a full-size 1/4" jack into a 3.5mm (1/8") Eurorack input—but the adapter's buried in a drawer, or worse, lost in the chaos of your studio floor? The ADDAC 200S is the answer to that exact frustration, and it lives right on your rack so it’s never out of reach. It’s not a synth, not a processor, not even an active circuit—just a passive, no-power-needed interface that converts three 1/4" inputs to 1/8" outputs, neatly tucked into a 4HP Eurorack module. It’s the kind of thing you don’t realize you need until you use it, and then you wonder how you ever patched without it.

Designed as part of ADDAC’s 200 Series—dedicated to analog CV utilities and practical modular helpers—the 200S slots into the ecosystem as a humble but essential workhorse. It doesn’t generate sound, shape envelopes, or modulate pitch. Instead, it removes friction. Whether you're integrating guitar pedals, line-level outboard gear, or studio monitors into your Eurorack setup, the 200S eliminates the need for dangling adapters or makeshift cable solutions that can pull loose or cause intermittent connections. The module features three independent 1/4" to 1/8" conversion channels, each with a sturdy jack on the front panel, so you can route multiple external signals directly into your modular system with confidence.

And while it may seem trivial on paper, the real value reveals itself in practice. Eurorack’s embrace of 3.5mm jacks has always created a minor but persistent barrier when interfacing with the wider world of audio gear, which still runs on 1/4". Most users end up with a tangle of adapters, some poorly shielded, others prone to wobbling out of place. The 200S solves that with industrial-grade jacks and a solid aluminum panel, mounted securely in your case. It’s not flashy, but it’s reliable—the kind of module you install once and forget, except for the times you silently thank it during a live set when your guitar pedal chain stays perfectly connected.

Specifications

Manufacturer	ADDAC System
Production Years	2023–present
Original Price	55.00 €
Format	Eurorack
Width	4 HP
Depth	35 mm
Power	Passive (no power required)
Function	1/4" to 1/8" (3.5mm) jack adapter
Channels	3 independent conversion paths
Input Type	1/4" (6.35mm) mono or TS
Output Type	1/8" (3.5mm) mono or TS
Electrical Type	Passive signal pass-through
Panel Material	Anodized aluminum
Available Colors	Black, Red (standard); custom colors available
Custom Options	Green, Blue, White, Silver Gray, Yellowed Silver, Dark/Light Bronze panels; print colors vary
Mounting	Standard Eurorack 3U panel
Weight	Approx. 100 g (module only)
Country of Origin	Portugal

Key Features

Three Independent 1/4" to 1/8" Conversion Paths

The 200S provides three dedicated channels, each converting a standard 1/4" jack to a Eurorack-compatible 3.5mm output. This means you can simultaneously connect a guitar, a drum machine, and a line-level effects return—all without swapping cables or daisy-chaining fragile adapters. The jacks are front-mounted, robust, and spaced to accommodate even large plugs, which is more than some DIY adapters can claim. There’s no crosstalk, no signal degradation—just a clean, direct pass-through. Since it’s passive, there’s no risk of noise injection, ground loops, or power draw complications. It’s as transparent as a piece of wire, but infinitely more convenient.

Passive Design, Zero Power Draw

One of the most underrated aspects of the 200S is that it requires no power at all. In a Eurorack system where every milliamp counts—especially in skiffs or portable cases—adding a module that doesn’t consume +12V, -12V, or +5V is a quiet luxury. It installs like any other module, takes up only 4HP, and disappears into the background, doing its job without demanding attention or resources. There are no circuits, no op-amps, no active components—just precision-machined jacks and internal wiring. That also means there’s nothing to fail electronically, making it one of the most reliable modules you can own.

Custom Panel Options for Personalization

While function is the focus, ADDAC doesn’t skimp on aesthetics. The 200S is available in standard black or red anodized aluminum panels, but the company offers a range of custom colors for those who want their utility modules to match their build’s theme. From deep bronze to bright yellow, and with print colors that contrast for readability, the 200S can be tailored to fit a color-coded system or just add a splash of personality to an otherwise utilitarian row. Custom panels take 4–6 weeks to produce and come at an additional cost, but for builders who treat their racks as both instruments and art pieces, it’s a welcome option.

Historical Context

The ADDAC 200S emerged in 2023 as part of a broader shift in Eurorack culture—one that’s increasingly valuing practicality alongside sonic innovation. For years, the format thrived on wild, experimental modules: FM beasts, granular manglers, chaotic sequencers. But as modular synthesis moved from niche hobby to professional tool, users began demanding more utility, more integration, and fewer headaches when connecting to the outside world. The 200S sits at the quiet end of that spectrum: not a sound generator, but a bridge. It reflects ADDAC’s long-standing philosophy of solving real-world problems in modular patching, a trait seen in other 200 Series modules like the ADDAC200 (2HP multiples) and ADDAC200RM (rails monitor).

While other manufacturers have released similar adapter modules—some with buffering, others with level shifting—the 200S stands out for its simplicity and build quality. In an era where many companies are adding DSP, MIDI over USB, and touchscreens to Eurorack, ADDAC chose to go the opposite direction: a module so basic it could have existed in 1970, if Eurorack had existed then. It’s a reminder that not every problem needs a complex solution. Sometimes, you just need the right jack in the right place.

Collectibility & Value

As a modern, low-cost utility module, the ADDAC 200S isn’t a collectible in the traditional sense—there’s no vintage premium, no rare run, no circuit revisions to hunt for. But that doesn’t mean it lacks value. At 55€ new, it’s an affordable insurance policy against patching frustration. Used units typically sell for 30–40€, depending on condition and whether they include original packaging. Since the module has no active electronics, failure is extremely rare—though bent jacks from improper insertion or case over-tightening are the most common issue. Buyers should inspect the alignment of the 1/4" jacks and ensure the 3.5mm outputs aren’t loose or wobbly.

Because it’s still in production, there’s no urgency to buy now, but its usefulness means it rarely stays on shelves for long at dealers. For builders assembling a new case, it’s often one of the first utility modules added. The custom panel option adds a small resale premium, especially for uncommon colors like dark bronze or silver gray, but mostly it’s a personal choice rather than an investment. If you’re buying used, verify that the module wasn’t modified—some users have attempted to add buffering or switching, which defeats the purpose of its passive design.