ADDAC System ADDAC710 (–)

Two channels of clean, transformer-isolated audio out, without the hum and without needing phantom power.

Overview

Some modular rigs sound great in the box and turn into a buzzing mess the second they hit a mixer, recorder, or PA. The ADDAC710 Balanced Outputs is aimed at that problem. It doesn't make sounds and it won't sequence anything. This 6 HP module takes two unbalanced modular signals and converts them to fully balanced outputs via XLR. A pair of audio transformers breaks ground loops and prevents impedance mismatches. That means no more 50 Hz hum creeping in from studio gear and no more noise when you go live.

ADDAC System built the ADDAC710 as part of their 700 series. It's a dual-channel isolated DI (direct input) box designed specifically for Eurorack. It isn't trying to color your sound. The core of the design is galvanic isolation: the input and output sides are electrically separated by transformers, so there's no shared ground path unless you want one. That's what kills ground loops, the usual cause of the low-frequency drone that gets louder when you plug in more gear.

It doesn't generate audio. Its job is to sit in the signal path and do nothing you can hear, which is how you know it's working.

Specifications

Manufacturer	ADDAC System
Model	ADDAC710 Balanced Outputs
Dimensions	6 HP
Depth	40 mm
Current Draw	40 mA +12V, 40 mA -12V, 0 mA 5V
Transformer type	unity 1:1 type Audio Transformer
Frequency range	20 Hz to 20 KHz
Output connectors	two fully balanced outputs (via XLR connectors)
Ground switch	LIFT/FLOAT/GND 3-way switch
LIFT position details	circuit will be “lifted” to ground through a 100R resistor and a 10nF capacitor
FLOAT position details	Ground will not be shared leaving ins and outs grounds completely apart from each other fully isolating both signals
GND position details	Ground will be shared between inputs and outputs, here no isolation is used
Phantom Power	+48V Phantom Power is NOT needed for the module to operate. Having Phantom Power ON won’t influence the module operation.

Key Features

Transformer-Based Isolation That Just Works

The ADDAC710 uses a pair of unity 1:1 audio transformers, one per channel. They break ground loops while keeping a full 20 Hz to 20 kHz frequency response. The two windings of each transformer are electrically insulated from each other, which gives true galvanic isolation between your modular system and whatever lies beyond the XLR cable. Your synth stays disconnected from the grounding schemes of mixers, audio interfaces, or live sound boards, which often introduce noise when tied directly together.

The manufacturer describes the transformer as a "low-cost" unit compared to the one in the ADDAC800X, and acknowledges that its frequency response isn't perfectly flat. There's a -0.2 dB attenuation at 50 Hz, which is likely inaudible in most real-world scenarios. In exchange you get a smaller footprint and a lower price.

Smart Grounding Control: LIFT, FLOAT, or GND

Each channel has a 3-way ground switch: LIFT, FLOAT, and GND. In GND mode, input and output grounds are tied together, so there's no isolation. That can be useful if you're feeding a device that expects a common ground and you're not hearing noise. In FLOAT mode, the grounds are completely separated. That's maximum isolation, and the one to try on stubborn hums. LIFT sits in the middle: the output is connected to ground through a 100-ohm resistor and a 10nF capacitor, which allows some grounding for stability while still breaking the direct current paths that cause noise. You can switch between them without opening your case or repatching cables.

Compact, Shallow, and Phantom Power Independent

At only 40 mm deep, the ADDAC710 fits shallow Eurorack cases where space is tight. That comes from using a smaller transformer than the one in the ADDAC800X, part of a deliberate redesign to reduce depth. It draws 40 mA on both the +12V and -12V rails, with zero draw on 5V. It does not require phantom power to operate. If your mixer sends +48V down the XLR cable, it won't affect the module's function, and the manual says so explicitly.

A Budget-Friendly Alternative to the ADDAC800X

The ADDAC710 exists as a more affordable, stripped-down sibling to the ADDAC800X High-End Outputs module. It shares the same mission—clean, isolated balanced outputs—but achieves it with a lower-cost transformer and a simplified design. It lacks some of the features of the 800X (though the exact differences aren’t detailed), but it retains the core functionality. For many users, that’s more than enough. If you’re building a portable modular rig or just want reliable outputs without spending top dollar, the 710 hits a sweet spot. It’s also set to be available as a full DIY kit, which will appeal to builders who want to save money or enjoy the hands-on process.

Collectibility & Value

ModularGrid currently lists the ADDAC710 at $189, which is treated as the primary price reference. Perfect Circuit lists a pre-order price of $219, suggesting potential fluctuations or regional differences. It's a new-release module with no known production start date or original launch price, so it's too early to assess long-term collectibility. There's no data on common failures, maintenance needs, or repair complexity, likely because it's a passive, transformer-based design with few failure points. The DIY kit option may influence availability and secondhand pricing down the line.