OSC strange behaviour

I’m developing some kind of super simple personal monitoring app using Open Stage Control. It’s for learning purpose but I’d love to see how it works in real studio situation.


I’ve managed to control foldback master gain, individual sends gain, name and fader position and changing from one FB to another.
However, I can’t expose the position of the playhead in BBT nor the session name. Besides, I added two “leds” that should light up when master record is engaged and playhead is running.
In order to debug this, I’ve tested with different configs but the problem seems to be in receiving this “messages” from Ardour. In fact, without changing the code and Ardour’s config, it worked as expected (leds light up properly, the session name was exposed except for playhead position) but then I restarted the session and it was buggy again.
I’d really appreciate some help and guidance.

You have to tweak which parameters you want to receive from ardour in the “default feedback” tab. Specifically, tick the “playhead position as bar and beat”, “strip controls” and “strip buttons”. And AFAIK you have to properly quit Ardour and the session for it to remember the settings. Note that you can force a custom feedback by sending Ardour the computed feedback number. That is what i do when dealing with OSC and Ardour.

Thanks Baptiste, I’m pretty shure that these feedback options were ticked but I’ll give it a try and see how it goes.

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Well… another day, another test xD

It didn’t worked out so I made a simple test code and record the screen. In the first video you can see how it works properly but then I close Ardour, stop Open Stage Control, restart all over and it fails as described above.
PS. I am using Ardour 8.6 demo from official download.


Both videos are private, i can’t watch them.

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You should be able to watch them now.

Some progress here :grinning:

As @lenovens suggested in a couple of old messages, I tested OSC messages using oscsend and oscdump. I tried different configs and, effectively, Ardour wasn´t sending /session_name neither /position/bbt.
Looking back in the manual, I’ve found this under “Control Surface Set Up”…


Blockquote Any time the /set_surface command is sent, the current bank is recalculated and if feedback is turned on, the values of each strip’s controls are sent (or refreshed) as well. This will also refresh the Master feedback setup.

This address, /set_surface, did the trick… I executed as my first command and things get synced.

Is updated, so anyone can give it a try and look the code inside. Though it’s functional, I come across with new problems, so keep in mind it can be buggy.

As a simple README… you should open a session in Ardour (create tracks, foldbacks and sends) and in Preferences > Control Surfaces Enable OSC and set up as follows.

Then launch Open Stage Control, set send to localhost:3819 select the MMMix.json in load and start the app.
Everything should work OK.

Thanks @baptiste, you were really kind with your feedback.

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