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AbletonOSC's start_listen/stop_listen pattern subscribes to Live property changes and delivers them as push messages

Concept L2First instrument J · Audio-visual integration & sync

For any readable property (tempo, volume, playing_slot_index, etc.), AbletonOSC provides three OSC addresses: get/ (one-shot query), start_listen/ (subscribe), and stop_listen/ (unsubscribe). When you call start_listen, AbletonOSC registers a Python callback on the Live object’s property-change notification, and immediately sends the current value. After that, every time Live changes the property, the client receives a push message at /live//get/ without polling. This is the correct pattern for driving continuous AV visuals — reacting to volume changes or clip launches without polling at 60fps. A listener must be explicitly stopped with stop_listen.

Examples

To receive volume updates for track 0: send /live/track/start_listen/volume 0. Track volume changes in Live immediately push to /live/track/get/volume with params (0, new_volume). Stop: /live/track/stop_listen/volume 0. For clip playback position: /live/clip/start_listen/playing_position 0 0.

Assessment

A student wants to update a visual parameter whenever a track’s mute state changes. Write the OSC message to subscribe. Which address and arguments will deliver the updates? How do they stop receiving updates?

Prerequisites — understand these first

Don't confuse with

Sources

“Changes to any Track property can be listened for by calling `/live/song/start_listen/<property>` - Responses will be sent to `/live/song/get/<property>`, with parameters `<property_value>`”
corpus · abletonosc-osc-control-interface-for-ableton-live-live-objec · chunk 4

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