Sending the tempo to a grandMA3 over OSC
Bench-read on 22 September 2026: a 90→130 BPM ramp swept the Speed Master in front of us.
The grandMA3 has no "BPM" input. It receives a command line on an OSC address, and that command is what locks a Speed Master to a tempo. WinShow formats it for you; what remains is to line up both ends.
- 01Open an OSC input on the consoleIn the grandMA3, enable an OSC input, note its port and its prefix. On the bench: prefix
WinShow, port 8000. The prefix is free, but it must be identical on both sides. - 02Open Settings → OSC Tempo in WinShowThe assistant runs in three steps: the console, checking the settings, then the proof.
- 03Name the consoleEnter its IP address, the port and the prefix, then the Speed Master to drive. If the console broadcasts its announcement beacon on the network, its address can be clicked from the list rather than typed.
- 04Run the proof rampWinShow sends a ramp from 90 to 130 BPM over four seconds. Watch the console’s Speed Master: it must sweep. During the ramp, normal sending goes quiet towards that address alone — two interleaved streams would make the Speed Master oscillate and manufacture the symptom of a fault.
- 05Answer the questionThe assistant simply asks whether the Speed Master swept. Yes: the destination is saved. No: troubleshooting opens, and its first suspect depends on what happened.
| Symptom | First suspect |
|---|---|
| The send leaves, no effect on the console | The prefix does not match |
| The send fails | The address or the port |
| The console does not appear in the list | The firewall on the WinShow machine, port 10670 inbound |
| The Speed Master oscillates | Two destinations aim at the same Speed Master — that is refused at construction, so check no other tool is sending |
Console detection is passive: WinShow listens for the beacon the grandMA3 broadcasts roughly every fifteen seconds, and sends nothing. A console that goes unheard drops off the list after forty-five seconds — an empty list beats an address that no longer answers.