I want to practise playing piano with my Sony WH-1000XM4 headphones while listening to music on YouTube, so that I can practise playing as if joining in with other musicians.
Now, the headphones work over bluetooth. That means I can listen to YouTube. however, the headphones cannot simultaneously accept the 3.5mm audio from the piano. I want to be able to listen to both. I can tolerate an audio delay from the PC but obviously not from the piano.
This leads me to the idea that I can mix the output. Maybe feed a 3.5mm input from the PC and the keyboard and feed the output as 3.5mm into the headphones?
What sort of equipment do I need to mix the audio? How about something like this - is it overkill?