ADDAC System 710 (2022–)

A box for a modular rig that kills ground loops and noise.

Overview

The ADDAC System 710 goes into a Eurorack case and does its job without being noticed. It isn't a sound generator, and it doesn't color your tone. It deals with the low hum, the crackle and the interference that creep in when a modular talks to the outside world. It's a dual-channel isolated DI box, so what leaves your system is what you created - no extra artifacts, no crosstalk, no ground loops.

ADDAC designed the 710 as a streamlined alternative to its earlier 800X High-End Outputs. It trades some audiophile-grade components for practicality and keeps the core performance. It's only 40mm deep, so it fits shallow skiffs and travel cases where space is tight. That makes it a favorite among gigging modular artists who want reliable, noise-free outputs without bulking up the rig. The heart of the module is a pair of audio transformers, one per channel, with a flat frequency response from 20 Hz to 20 kHz. They give galvanic isolation, meaning no electrical continuity between the synth and whatever it's plugged into - PA, audio interface, mixer, tape machine - so ground loops get cut before they cause trouble. It all fits in a 6HP panel.

Specifications

Manufacturer	ADDAC System
Production Years	2022–
Original Price	€138 (kit)
Format	Eurorack
Width	6 HP
Depth	40 mm
Power Consumption +12V	40 mA
Power Consumption -12V	40 mA
Channels	2
Output Type	Balanced (XLR)
Input Type	Unbalanced (1/4" TS)
Transformer Type	Audio, 1:1 impedance matching
Frequency Response	20 Hz – 20 kHz
Isolation	Galvanic, transformer-based
Ground Switch	LIFT/FLOAT/GND (3-way per channel)
DIY Kit	Yes (SMD and through-hole)
Panel Color	Black anodized aluminum
Mounting	Standard Eurorack 3U

Key Features

Transformer Isolation That Just Works

The 710’s magic lies in its pair of audio transformers, each handling one channel with a clean 1:1 signal transfer. These aren’t high-gain amplifiers or tone-shaping circuits—they’re passive, transparent conduits that block DC and eliminate ground loops by breaking the electrical connection between your modular and downstream gear. This is critical when connecting to mixers, audio interfaces, or PA systems that share different ground potentials. Without isolation, you get hum, buzz, or even damaging current flow. The 710 stops that cold. The transformers are rated for full audioband response, so there’s no roll-off or phase shift within the audible spectrum. What you send in is what comes out—just cleaner, quieter, and balanced.

Ground Management with a 3-Way Switch

Grounding problems differ from rig to rig, so each channel has a 3-way LIFT/FLOAT/GND switch. In LIFT mode, the ground is connected through a 100Ω resistor and 10nF capacitor, which drains stray noise without creating a full loop. FLOAT disconnects the grounds completely, which suits linking systems with incompatible grounding schemes. GND ties the input and output grounds together, useful in a controlled environment where you want a common reference. Most users cycle through the three during setup until the hum vanishes. This level of grounding flexibility is rare in a module this size.

Compact Design for Real-World Use

At 40mm deep, the 710 is skiff-friendly, which matters to Eurorack users building portable systems. Many isolation solutions are deeper and force compromises in case selection or power supply clearance. ADDAC re-engineered the circuit from the earlier 800X to use a smaller transformer, which trims depth without sacrificing isolation quality. The front panel has two input jacks, two XLR outputs and the dual 3-way switches. No LEDs, no extra knobs. The panel is black anodized aluminum, it feels sturdy, and the jacks are securely mounted.

Historical Context

The ADDAC 710 arrived in 2022, part of a shift in Eurorack from purely sound-generating modules to utilities that solve integration problems. As modular systems grew more complex and showed up in live and studio settings, clean, professional-grade outputs became necessary. Many users patched into audio interfaces or mixers and got hum, buzz or signal degradation. Some turned to external DI boxes, but those added clutter and cabling. ADDAC's answer was to put pro audio isolation directly in the rack. The 710 sits in the 700 series, dubbed "Analog Heritage," though it's less about vintage tone and more about vintage reliability - it uses time-tested transformer isolation instead of active buffering or digital conversion. It competes indirectly with modules like the Intellijel Linus or the Mutable Instruments Yarns (in output mode), but those don't offer galvanic isolation. The closest analogs are standalone DIs, and none of them fit in 6HP.

Collectibility & Value

The 710 isn't a collector's item in the traditional sense. It has no rare components, limited runs or cult status. It is becoming a staple in touring and studio Eurorack setups. As of 2024, new DIY kits sell for around €138, and assembled units occasionally turn up used for €160 - €200. It's a passive module with no active ICs or delicate tuning, so failure rates are extremely low. The most common issue is incorrect assembly by DIY builders, especially reversed power polarity during installation. Always test with a multimeter before powering up. The kit includes both SMD and through-hole parts and is rated "easy/medium" difficulty, so beginners should proceed with caution. There are no user-serviceable parts once built, and the transformers aren't replaceable without significant rework. When buying used, check for bent jacks or cracked solder joints. Otherwise a working 710 should last indefinitely.