Light desks · alphaLJ Link: ChamSys MagicQ

LJ Link is an independent program that works with ChamSys MagicQ. It is not a product of, or endorsed by, ChamSys.

A tap on every beat for Tap to Time. Untested.

How it works

MagicQ has no OSC address that sets a BPM. What it does take is a tap: an OSC message that you map to Tap to Time in the macro window. So LJ Link taps for you: on every beat of the deck under SEND BPM it sends an OSC message without a value to the address you choose. MagicQ works out the tempo from the taps, like a DJ tapping, but exactly on the beat grid of the player, with pitch included.

Step by step

1. On the MagicQ desk or PC

1. OSC needs a fully unlocked MagicQ (consoles except MQ40 and MQ40N, and MagicQ PC).

2. Setup → View Settings → Network: set OSC Mode to Rx (or Tx and Rx) and note the OSC Rx Port. Port 8000 is a good choice.

3. Open the Macro window and switch to the Autom view. Add a row: type OSC Message, in the column P1 the address /tap (up to 15 characters).

4. Set the action of that row to Tap to Time for the playback whose speed should follow, or to Global Tap to Time, if your software version offers it.

2. In LJ Link

1. Menu (☰) → Light desk link → ChamSys MagicQ (OSC taps) – Alpha.

2. Address of the MagicQ computer or desk (same computer: 127.0.0.1), the port from step 1 (8000).

3. The OSC address is the one from the Autom row: /tap. For several playbacks or actions enter several addresses separated by commas, for example /tap1, /tap2, /tap3: each beat then sends one message to each, because MagicQ uses one OSC message for one action only. Add one Autom row per address.

4. Save, then Send test: eight taps at 120 BPM, one every half second. In MagicQ the speed should settle at 120 BPM after a few taps.

5. Load a track, play: the deck under SEND BPM taps on every beat.

What is sent

• A standing deck sends no taps. MagicQ keeps its last tempo.
• After a cue, loop or track change the taps resume on the next beat; MagicQ needs a few taps to settle again.
• The demo only sends when Send demo data is ticked in the light desk settings (since 1.7.2, off at every start).
• OSC goes by UDP: nothing is reported if MagicQ is not listening. Check OSC Rx and the port on the desk.

What is not known yet

• Whether Tap to Time and Global Tap to Time can be put on an OSC message in your version, and which action is best for a speed master.
• How many taps MagicQ needs to follow a tempo change, and how it reacts to taps that stop.
• Whether another action of MagicQ takes a BPM directly, for example through the remote command /rpc. If you know one, please tell us.

Idea and first draft of this output: soiza on GitHub. Thank you!