ADDAC System: ADDAC219IN Stereo > Dual Mono

This is an introduction to the ADDAC219IN Stereo > Dual Mono by ADDAC System, available at Takazudo Modular.

The ADDAC219IN Stereo > Dual Mono is an interface module that separates external line-level stereo signals into individual left and right mono outputs. It accepts a 3.5mm stereo TRS jack input, internally splits the signal into left and right mono, and outputs each through independent 3.5mm mono output jacks. It also boosts line-level signals to Eurorack level. With two conversion sections, this module serves as a bridge between external gear and your Eurorack system.

This product is available for purchase below.

• Product Photos
• Splitting Stereo Into Dual Mono
• Adjusting Audio Level Differences
• Examples of Gear With 3.5mm Stereo TRS Audio Output
• Related Products
• Technical Specifications
• Included Accessories

Product Photos#

Splitting Stereo Into Dual Mono#

This module’s function is straightforward — exactly as described above: Split stereo into dual mono. Boost the level and output it ready for modular use!

Even when building a Eurorack system, you will often want to use other gear alongside it. For example, our shop carries the following as standalone audio devices:

• Meng Qi: Wingie2
• Recovery Effects And Devices: The Mystic

The latter, The Mystic, has a mono output and can be connected directly to a Eurorack system. However, Wingie2’s output is stereo — audio out via a TRS cable carrying combined L/R signals. To connect this to a Eurorack system, you need to convert it to mono.

In such cases, you would need a cable that splits stereo into two mono signals, but having a dedicated module pre-installed in your setup keeps things tidy.

Adjusting Audio Level Differences#

The ADDAC219IN does not just convert stereo signals to mono — it also adjusts audio signal level differences.

Audio signals exchanged between Eurorack modules are around +/-5V, while other gear typically operates at +/-2V or less. In short, the signals exchanged between Eurorack modules are a bit too hot for most electronic instruments.

This is due to historical differences in how instruments evolved — most electronic instruments handled audio waveforms at +/-2V or less, while Eurorack modules adopted +/-5V. Because of this voltage difference, you may notice that audio from external music gear sounds too quiet when brought into a Eurorack system.

This is where the ADDAC219IN’s ability to boost the level of audio imported from external gear comes in handy. This module handles the level adjustment simultaneously — a welcome convenience.

Examples of Gear With 3.5mm Stereo TRS Audio Output#

Music gear that outputs audio via a 3.5mm stereo TRS jack includes products such as:

• Teenage Engineering: OP-1 Field
• Korg: Volca series
• Bastl Instruments: Kastle

Devices with 3.5mm stereo TRS jacks tend to be smaller, gadget-style instruments. Additionally, since standard small headphone jacks are 3.5mm stereo TRS, this module could also be useful when you want to quickly bring audio from a PC or smartphone into your Eurorack system.

So whenever you want to bring something from outside your modular into the system, this is a great module to have on hand.

Related Products#

The reverse of this module — one that combines dual mono into stereo — is also available from ADDAC System, and we carry it as well.

• ADDAC System: ADDAC219OUT Dual Mono > Stereo

Please check that out as well.

Technical Specifications#

• Width: 3HP
• Depth: 40mm
• Power consumption: 20mA +12V / 20mA -12V / 0mA +5V

Included Accessories#

• Power ribbon cable
• Screws

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