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  • Connects to DB25 or TRS modules to provide direct audio inputs
  • Connects to Xcelon mixer and expanders for fifteen stereo direct outputs
  • Bidirectional signals on twenty-four mono and three stereo 3.5 mm jacks
  • Passive circuitry requires no power

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Direct multi-channel expansion

IO is part of Boredbrain’s direct multi-channel audio series of modules, which interconnect to provide a multitude of audio outputs to eurorack systems. IO can be used as signal inputs for the DB25 and TRS modules, or alternatively to provide the Xcelon mixer with up to fifteen stereo direct outputs at eurorack level.

Flexible Interconnection

On the front of the module are twenty-seven 3.5 mm jacks, which can serve as either inputs or outputs depending on how the rear ports are connected. The first twenty-four are mono, and the last three are stereo, with numbers above each jack (1-30) corresponding to those on the rear input/output ports.

The five connection ports on the back of the module (IN/OUT 1-6, 7-12, 13-18, 19-24, 25-30) can each send or receive six signals to or from compatible Boredbrain modules using the supplied 8-pin ribbon cables. When these ports are connected to the DB25 or TRS modules, the IO front jacks act as signal inputs for those modules. Alternatively, when connected to the Xcelon mixer or XP3 channel expander (PRE or POST or both), the IO front jacks act as eurorack-level direct outputs for the stereo mixer channels. The connections to these ports can be mixed and matched in any order with compatible modules connecting to any of the ports.

Common Configurations

12 mono balanced line outputs

This simple configuration allows for twelve TRS outputs, and may be expanded further using the remaining three ports (eighteen signals) on the IO module.

IO + DB25
24 mono balanced line outputs

This high-density configuration allows for a large number of balanced outputs, and still has one remaining port (six signals) on the IO module.

24 mono balanced line outputs

This configuration doubles the number of balanced TRS outputs by introducing an additional TRS module to the setup.

15 stereo eurorack direct outputs

This configuration provides eurorack-level direct outputs for the entire Xcelon mixer system. Signals can then be selectively patched from IO into an audio interface or to other destinations.

9 stereo eurorack direct outputs + 12 mono balanced line outputs

This configuration uses the IO module for both direct outputs and inputs simultaneously. The first three banks provide eurorack-level direct outputs for the Xcelon mixer, while the last two banks provide inputs for the TRS module. The IO module can then be selectively patched to itself or accept other signals to feed the balanced outputs.

NOTE: These configurations represent the most common scenarios. More may be possible by combining select modules in the Xcelon and Direct Multi-Channel Audio series.

Boredbrain Direct Multi-channel Audio Series
Direct Multi-Channel Audio Series

technical specs

  • Width: 8 HP
  • Depth: 0.79 in (20 mm)
  • Weight: 3.0 oz (86 g)
  • Power: None (passive)