ADDAC System ADDAC200PI (2015–)

A no-frills, no-noise gateway between your modular and your pedalboard—finally, a send/return that doesn’t make you choose sides.

Overview

You know that moment when you’ve got a sweet Eurorack rig humming, a gorgeous Mutron III on the floor, and you just want to patch it in without frying your modules or losing half your signal? That’s where the ADDAC200PI steps in—not with fanfare, but with quiet competence. It doesn’t generate sound, modulate it, or mangle it. Instead, it does something rarer in the modular world: it gets out of the way. This is a dual-channel pedal integrator, built to bridge the impedance and level gap between modular gear and guitar pedals. And it does it with surgical precision, zero fuss, and a footprint so small it barely registers on your rack.

At just 4HP wide, the ADDAC200PI is the kind of module you install and then forget—until you realize you can’t imagine life without it. Each channel handles send and return independently, with proper level scaling: the send side attenuates modular-level signals (around ±5V) down to instrument-level (roughly -10dBV), which is what your pedals expect. On the return, it boosts the weaker pedal output back up to modular levels, so your filters, mixers, and VCAs don’t starve. No more noise floors creeping in, no more clipping on the way out. It’s not magic—it’s just correct engineering.

And while it’s marketed as a pedal interface, owners quickly discover it’s more versatile than that. Some use it to bring line-level gear like drum machines or audio interfaces into the rack. Others repurpose it as a compact headphone amp (yes, really—one channel, mono, but it works). It’s become a stealth utility, the kind of module that shows up in 900+ ModularGrid racks not because it’s flashy, but because it solves a real problem that most modules ignore.

Specifications

Manufacturer	ADDAC System
Production Years	2015–
Original Price	€100 / $120–134
Width	4 HP
Depth	30 mm
Power Consumption	10 mA @ +12V, 0 mA @ -12V, 0 mA @ 5V
Function	Dual Channel Send/Return Pedal Integrator
Send Attenuation	1:20 (÷20)
Return Gain	20:1 (×20)
Send Connectors	1/4" TS, 1/8" TS (dual jacks per channel)
Return Connectors	1/4" TS, 1/8" TS (dual jacks per channel)
Input Signal Level (Send)	Modular Level (±5V)
Output Signal Level (Send)	Instrument Level (-10dBV)
Input Signal Level (Return)	Instrument Level (-10dBV)
Output Signal Level (Return)	Modular Level (±5V)
Internal Circuitry	Based on TL072 op-amp
DIY Availability	Yes, kit available for €64 (excl. VAT)
Front Panel Options	Black (standard), custom colors available (Red, Green, Blue, White, Gray, Bronze, etc.)

Key Features

Dual Independent Channels with Flexible I/O

Two full send/return paths mean you can run stereo effects or keep two separate pedal chains—one for time-based effects like delay and reverb, another for filters and modulation. Each channel has both 1/4" and 1/8" jacks, so you’re not forced to carry adapters or sacrifice pedalboard real estate. Plug in your full-sized guitar cables on one side, a compact boutique pedal with mini-jacks on the other—this module doesn’t care. The dual jacks are wired in parallel, so you can daisy-chain or switch between devices on the fly. It’s a small thing, but in a live setup, it’s the difference between a smooth transition and a crouching cable struggle.

Precise Level Matching, No Guesswork

The magic isn’t in complexity—it’s in calibration. The send path cuts the signal by a factor of 20, bringing that hot modular output down to a safe instrument level. The return path applies a 20x gain boost, restoring the weaker pedal signal to full modular strength. This isn’t an approximation; forum testing and manufacturer confirmation confirm the exact ratios. That precision means no noise penalty, no signal starvation, and no clipping. It’s transparent—exactly what you want from a utility module. No EQ coloring, no added saturation (unless your pedals bring it), just clean, reliable translation between worlds.

Minimal Power Draw, Maximum Rack Efficiency

Running only 10mA from the +12V rail and nothing from the -12V or 5V, the ADDAC200PI is a power sipper. In a system where every milliamp counts, especially in smaller cases, that’s a real advantage. You can slap this into a 32HP case with a modest power supply and never worry about overloading the negative rail. It’s also dead silent—no hum, no crosstalk, no ground loops—assuming your build or unit is healthy. The circuit relies on the TL072, a tried-and-true JFET op-amp known for low noise and high input impedance, making it ideal for this kind of buffering task.

Historical Context

When the ADDAC200PI launched around 2015, the Eurorack boom was accelerating, but integration with the wider world of effects was still clunky. Most modular users either avoided pedals entirely or jury-rigged solutions with mixers, attenuators, and line drivers—wasting precious HP and introducing noise. ADDAC System, a Lisbon-based boutique builder known for blending analog and digital concepts, saw the gap and filled it with surgical precision. They didn’t reinvent the wheel; they built the wheel correctly.

At the time, few manufacturers offered dedicated pedal interfaces. Doepfer’s A-138d came close but lacked the dual mini/macro jacks and compact footprint. The ADDAC200PI carved its niche by being both minimal and complete—no extra features, no digital control, just two clean channels that did one job extremely well. It arrived as modular setups grew more complex and performers sought ways to integrate familiar floor-based gear. Suddenly, your entire pedalboard wasn’t obsolete—it was an extension of your synth.

This was also the era when DIY culture surged in Eurorack. ADDAC leaned into that by offering the 200PI as a kit. At €64 (excl. VAT), it was accessible to builders, and the assembly guide is clear, well-illustrated, and beginner-friendly. That move didn’t just expand availability—it built community. Soldering your own 200PI meant understanding its function at a component level, and that kind of ownership breeds loyalty.

Collectibility & Value

The ADDAC200PI isn’t a “collector’s item” in the traditional sense—no limited editions, no celebrity endorsements, no legendary sound. But it’s quietly become a staple, and that reliability has its own market value. New units sell for $120–$139 depending on the retailer, with Reverb and Perfect Circuit listing them around $135. Used prices hover between $80 and $110, reflecting its utilitarian status—nobody overpays, but good units don’t linger.

Because it’s a passive signal handler (aside from the op-amp), failure points are minimal. The most common issues are mechanical: damaged jacks from repeated plugging, or loose panel screws. The TL072 op-amp is robust, but like any IC, it can fail—though reports are rare. Units that hum or cut out should be checked for cold solder joints, especially on the power header or jacks. Given its simple design, repairs are usually straightforward for anyone with basic soldering skills.

If buying used, test both channels with a known-good pedal chain. Check for consistent signal level, no crackling, and no channel imbalance. Also verify the power draw—anything pulling more than 10mA on the +12V rail suggests a problem. Since the module draws nothing from the -12V, a damaged negative rail connection won’t affect operation, but it could indicate broader power distribution issues in the case.

The DIY kit remains available, which keeps prices in check. You won’t find vintage premiums or scalpers hoarding 200PIs—this is gear for users, not speculators. But that’s a compliment. In a market full of overdesigned, overpriced modules, the 200PI endures because it’s honest, functional, and fair-priced. It’s the anti-hype module.