I'm not sure if it's the same, but if I listen to pure noise (to sleep or something) I can somewhat adjust my hearing to focus on certain frequency bands in the

I'm not sure if it's the same, but if I listen to pure noise (to sleep or something) I can somewhat adjust my hearing to focus on certain frequency bands in the uniform noise making me to hear a ringing sound in the noise. I can adjust the pitch and it will stay at the pitch until I change it. So with this I can play a melody with the ringing noise. Sometimes I do this until I fall asleep. :-)