After some years of using and watching Luppp I decided this year to get into development of this project to. Like in any other open source project, there is a lot of stuff to do. So I red a lot about C++ and started by fixing simple stuff and got deeper and deeper into the project and the source code. While investigating how all this works, I generated some documentation and graphs to understand. I want to publish my graphs about the signalflow of Luppp know since this might be interesting for someone.

Input Section

At first lets look at the input section of Luppp. There is a stereo input available. You can connect anything to these ports to create loops live pretty easy. Anyway, there are a lot of options how to route the signal internally. But lets see:

The orange rectangle symbolizes the Jack ports. So this is the source of the signal for Luppp. Than you have a vertical fader to adjust the gain of the signal. You can also double the level. Its located in the top right corner of the Luppp window.

The adjusted signal goes from the fader to the "Clip Recorder", which is the point where clips get recorded and stored in the grid.

Additionally the signal goes through the Sidechain volume knob to the sidechain signal output of Luppp. So you can apply some sidechain compression or whatever on the input signal. If you want and activate the "Key"-Button in the top right section of Luppp, you can also use the input signal as controlling signal for the sidechain effecting.