AI Synthesis: AI026 Line I/O Interface

This is an introduction to the AI026 Line I/O Interface by AI Synthesis, available at Takazudo Modular.

The AI026 Eurorack Line Interface converts between line-level signals (approximately +/-2V) and the signal levels commonly used by Eurorack modules (approximately +/-5V) through gain and attenuation. This allows you to boost low-voltage line-level signals to standard modular synth levels, or perform the reverse.

It is available in two panel versions — aluminum and black — and we also carry DIY kits.

This product is available for purchase below.

• Product Photos: Assembled
• Product Photos: DIY Kit
• Features of the AI026 Line I/O Interface
• Panel Description
• Reference Video
• Technical Specifications
• DIY Guide

Product Photos: Assembled#

Product Photos: DIY Kit#

Features of the AI026 Line I/O Interface#

The output voltage of music equipment varies from device to device. When I briefly looked into what typical levels look like, I found that, for example, the Behringer TD-3-SR, an affordable bass synth, outputs approximately +/-2.75V peak from its OUTPUT.

In contrast, the voltage flowing through patch cables in a typical modular synthesizer is often within the +/-5V range. Because of this, when receiving output from music equipment into a modular synth, the volume may feel unusually low. This is because the voltage swing representing the audio data from that equipment’s output is small. This is not a matter of better or worse — it simply results from different manufacturers building to their own specifications.

Conversely, when receiving modular synth output on another piece of music equipment, the sound may be far too loud. For example, plugging headphones directly into a modular synth’s VCO output would produce a shockingly high volume*. The AI026 Line I/O Interface is a module designed to adjust these volume differences.

* We don’t recommend trying this, as it could damage your ears or headphones.

For Example, Wingie2#

Among the products we carry, the Wingie2 has a line output, and you can connect this jack’s output to other modular synth modules to use Wingie2’s audio within your modular system. While I haven’t measured it precisely, my impression is that Wingie2’s line output level seems lower compared to other modular synth modules. In such cases, using this AI026 allows you to amplify Wingie2’s output to the larger +/-5V voltage range used by modular synths.

Additionally, Wingie2 also accepts external audio via line input. If you try to feed modular synth audio into it, the volume may be too high for Wingie2 to handle properly. Wingie2’s manual advises against inputs that are too loud, and feeding the high voltage of a modular synth directly could result in clipped audio. The AI026 can also be used in this scenario to attenuate the modular synth’s output.

In this way, when incorporating other music equipment into your modular synth setup, having one AI026 enables seamless audio level adjustment.

Panel Description#

Each section of this module serves the following purpose.

1. LINE LEVEL Control

This knob adjusts the level of the signal received at LINE LEVEL IN. At the 3 o’clock position, it is at 100%. Turning it further to the right amplifies the input signal beyond 100%. This amplification can be used to boost quiet, unnormalized audio, or to apply a saturation effect to the input signal.

2. EURO LEVEL Control

This knob adjusts the volume of EURO LEVEL IN. At fully clockwise, it is at 100%.

3. LINE LEVEL IN

The two input jacks can receive a stereo line-level signal. The left input is normalled to the right, so if no cable is plugged into the right input, the signal received by the left input is also passed to the right.

4. EURO LEVEL IN

The two input jacks can receive a stereo Euro-level signal. The left input is normalled to the right, so if no cable is plugged into the right input, the signal received by the left input is also passed to the right.

5. LINE LEVEL OUT

These are the line-level outputs of the Euro-level input signal.

6. EURO LEVEL OUT

These are the Euro-level outputs of the line-level input signal.

Reference Video#

Below is an official demo video from AI Synthesis. You can see it converting between +/-2V output from Ableton Live and +/-5V output from a modular synth.

Technical Specifications#

• Width: 4HP
• Depth: 22mm
• Power consumption: 11mA +12V / 11mA -12V / 0mA 5V

DIY Guide#

The DIY kit includes the panel, PCB, all components, power ribbon cable, and mounting screws. This kit contains small surface-mount components (SMD parts), making the DIY difficulty level relatively high. We recommend assembling with a fine-tipped soldering iron, solder wire of 0.6mm diameter or less, and a magnifying glass.

AI Synthesis provides detailed DIY guides on their website. The guide linked below includes an assembly video along with step-by-step instructions with photos, making it a great resource for those new to DIY as well.

• AI026 Line I/O Interface Build Guide

Assembly Impressions#

I, Takazudo, also assembled this kit myself. This DIY kit is primarily composed of SMD components, and it may be difficult to assemble unless you have considerable experience with through-hole soldering at a minimum. The number of parts is not too large, and there is sufficient space between components for the soldering iron, but you should approach it as an introduction to SMD soldering.

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