ABY – MIDI Controlled TRS ABY Box

The Oscillator Devices ABY is a MIDI controlled, bidirectional TRS ABY switch. That means that you can use it both ways and it means that you can use it with TRS plugs and stereo signals.

The ABY is true bypass, which means its signal path is passive. So, no buffers in the way, straight relay based signal path.

Features:

  • True bypass ABY box
  • TRS support
  • MIDI Control with MIDI In and MIDI Thru
  • Control with CC messages or with PC and presets
  • Very small footprint (93mm x 39mm) and only 32mm in height
  • Fully supported by the WebMIDI Interface
  • Compatible with all MIDI 1.0 compliant controllers
  • High-quality Neutrik sockets
  • Developed and built by Oscillator Devices in Germany

ABWhat?!

What is an ABY box, anyways? Easy, it either switches one output between two inputs, or one input between two outputs. Because of its passive design, the Oscillator Devices ABY can do both. You can do several things with it:

  • Switch between two guitars
  • Switch between two amps
  • Switch between two effects chains

Stereo Switching

The ABY works with TRS plugs and can route stereo signals. Of course it can be used with TS cables and mono signals, too. But be aware, that the ABY can’t switch stereo signals independently. That means, that tip and ring are always connected to the same in/output.

Presets

Do I really need presets? That depends on your setup. Years of experience with MIDI setups have shown us that no two are the same. There are MIDI controllers, for example, that can only send PC messages. Or, some setups have programmed presets for every song and only a single PC message is sent, to set up all devices for that song. For that, you can setup the ABY for all 127 PC commands how you like it.

Setting up a preset is as easy as it can get. Set the ABY how you like it using the switch. Hold the switch until it flashes. Send the PC command to which you want the setting to be saved. Done.

Commands

There are various CC commands to control the ABY, so you can use it like you want it. You can either set it to a certain state (A on + B off, A off + B on, A on + B on), enable, disable or toggle A or B, or you can cycle through the states.

Made for Pedalboards

The HYDRA4X is made for pedalboards where room is key. On most pedalboards, utility devices like power supplies and loop switchers are mounted under the board to leave the precious space on the top for the real stars: The Pedals.

For that reason, the height of the HYDRA4X is reduced to what is physically possible with stacked jacks. Also, the buttons on top can be locked, so no unwanted changes can happen, when mounted under the board.

MIDI Connection

The MIDI connections are assigned according to the official MIDI specification of MIDI TRS using MIDI TRS Type A, like pedals from Boss or Wampler. A 1/8″ (3.5 mm) stereo jack plug is used.

MIDI TRS to 5-PIN
1/8″ stereo jack plug to DIN 5-Pin according to MIDI TRS Type A

Media

Documentation

DocumentVersionDownload
User ManualHYDRA4X 1.0 (February 2025)PDF
Quick StartHYDRA4X 1.0 (February 2025)PDF
LegacyHYDRA2E and HYDRA4 1.0 (August 2023)PDF
LegacyHYDRA2E and HYDRA4 1.0 (August 2023)PDF