Hey hey, I want to record MIDI into a sequencer application, using RtMidi. My understanding is: inside that application's tracks events are directly stamped with delta times, measured in ticks, since the last event in that track. Internally the sequencer runs a clock at a high rate (480PPQ or higher). It's probably best to "quantise" events to that internal clock while they are recorded. So the track object, with its connected MIDI input device, must be linked to the clock, which will wake up, whenever it is time for a tick. Linked meaning there must be some way to exchange relevant info (one of them owning a reference, callback, shared data, ...) If that basic, and simplified, principle is sound. Which solutions have been proven feasible to achieve that? For example: make every active track a thread and have a global mutex? Each track registers a callback function with the clock to store events. ...? RtMidi's input object (RtMidiIn) offers to register a callback function, that will be called with a received MIDI message, when input is available. Such messages could be stored in a container and be delivered when it's tick time. -- So again, a track might own a reference to the Clock thread object and query the current tick count since the last record start command and use that information to calculate the correct delta. Not sure though, whether that might raise issues with execution times. Using an atomic variable as a tick counter will avoid having to use mutex locks, at least. Is there any practical advice? Something based on experience? A good read? Best wishes and thanks, Jeanette -- * Website: http://juliencoder.de - for summer is a state of sound * Youtube: https://www.youtube.com/channel/UCMS4rfGrTwz8W7jhC1Jnv7g * Audiobombs: https://www.audiobombs.com/users/jeanette_c * GitHub: https://github.com/jeanette-c But now I'm stronger than yesterday <3 (Britney Spears)