Ardour Plugin on Multiple Tracks

Hi everyone… Sorry if this is a simple solution but, I would like to create a lowpass filter for all tracks except for a few vocal lines in a project I’m working on. I realize I can create a buss and route stuff there. But that would simply add additional audio as I understand it, I don’t want extra sound, I merely want a single filter’s automation to control ~20 tracks (and I can’t use the Master track due to a few tracks needing to not have the filter applied). Thanks in advance!

To avoid additional audio just send the outputs of those specific tracks to the bus track ONLY with that specific effect, just make sure the bus track outs are going to master in and the tracks to that bus in ONLY and none to master in. If you create sends and inserts then you will have aditional audio in the mix since this is a more complex routing path and way to control fx levels, but for simplicity just do as I say and you’ll be fine.

I hope you understood me and I understood your question.