NEXUS sits between your sources and your speakers. NEXUS takes up to four sources, sends them to three outputs, and runs a room correction on every output. After reading this chapter you will know what NEXUS does, what came in the box, and what else you need before you start.
What NEXUS does
NEXUS corrects your speakers in your room. Omnissiah, the free app that sets up NEXUS, plays test noise through each speaker and records it with a measurement microphone at your listening position. From that recording Omnissiah calculates EQ, delay, level and phase settings for each output and writes them into NEXUS. The correction targets the low end, where room modes cause peaks and dips that acoustic treatment struggles to reach. The correction also time-aligns your speakers with each other and with a subwoofer.
NEXUS switches sources and speakers. Two analogue inputs, a 3.5 mm aux input, S/PDIF and USB audio all arrive at one routing matrix, and you choose what reaches each output. With a MIDI or OSC controller, one button press changes the source or the live speakers.
NEXUS runs without a computer. Every setting is stored in NEXUS. Once the correction is written, NEXUS keeps working with the computer asleep, switched off or disconnected, powered from any 5 V USB-C supply.
NEXUS adds 0.85 ms. The processing delay from analogue in to analogue out is 0.85 ms, so you can track and monitor through NEXUS.
What NEXUS does not do
Each item below is a limit of the design. Knowing the limits up front saves a wrong wiring plan.
- Three outputs is the limit. Output 1-2 is a stereo pair and Output 3 is one more channel: a subwoofer, a mono speaker or a utility feed. Two stereo pairs plus a sub is not a supported layout.
- The measurement microphone never plugs into NEXUS. A measurement mic is XLR and needs 48 V phantom power, so it connects to your computer through an audio interface.
- NEXUS does not receive MIDI or OSC itself. Omnissiah, running on the computer, receives the control messages and drives NEXUS. Controllers get nothing back: no levels, no status lights.
- USB and S/PDIF share one input pair. Each has its own level and mute, but they reach the outputs together as the Digital pair (Chapter 7 — Routing & sources).
In the box
- 1 × NEXUS
- 1 × USB-C cable, 1 m
If you bought NEXUS with a measurement microphone, the microphone comes in its own box.
What else you need
- A computer to run Omnissiah. Omnissiah runs on macOS 11 or later. Check tantrumaudio.co.uk/downloads/omnissiah for other platforms.
- A measurement microphone. Any measurement microphone works. If yours came with a calibration file, Omnissiah can load it (Chapter 6 — Measuring & correcting).
- An audio interface with 48 V phantom power for the microphone.
- A mic stand, so the microphone stays still at head height.
- Cables for your speakers: balanced TRS jack leads for Output 1-2 and Output 3.
