Okay, that video. This was an early video and there may be some differences in current functionality.
Early on we had it set up so that the "function" buttons (Togl A, Velo B, Pres C, Tilt D) could output MIDI messages, so we were able to use it to turn things on/off. Now, these "function" buttons don't output MIDI and are hard coded to just perform their assigned duty — Togl A turns toggling on/off, Velo B turns velocity response on/off, Pres C turns pressure on/off, and Tilt D turns tilt on/off.
Also, in this video Velo B wasn't actually turning the arpeggiator on/off (it was on the entire time), it was actually starting the whole Live set (pressing the play button) and we set it up to blink along with the tempo (which is no longer possible).
If you want to set something up similar to this:
1. You'll need to turn off Local LED control (so the keys don't light up when you press them) — just open up the editor and uncheck the "Local" option in the LEDs Local/Remote section. Save and send the preset. Repeat this for any of the other presets you want this on.
2. Open up Ableton
3. Open Ableton's MIDI Sync preferences and make sure Track and Remote are turned ON for "Input: QuNexus (Port 1)" and just Track for "Output: QuNexus (Port 1)"
4. Create a MIDI track and drop the Live arpeggiator on it — this will be the track that controls the LEDs on the QuNexus
5. Set both "MIDI From" and "MIDI To" to QuNexus (Port 1) (sounds weird, but trust me)
6. Duplicate this MIDI track so you now have two MIDI tracks with the exact same settings
7. Drop whatever synth/instrument you want making the sounds onto this new duplicate track
8. Everything should be good to go now — the arpeggiating notes should be lighting up on the QuNexus and you should be hearing arpeggiated sound.
If you want the notes toggling like they are in the video, just make sure toggling is enabled (hold down the Togl A button until it lights up solid).
This method won't have an LED flashing along with the tempo, but everything else is the same.
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