Well, that one was hard :) I played on normal mode and wasted almost 8 minutes to tune the almost flat sine/triangle waive (it was not only me as I see from other comments) :P I still liked it, reminded me of uni times when I played with oscilloscopes during some lab lessons. I loved the tutorial, that was very straightforward and descriptive. It was engaging and challenging, despite being pretty simple puzzle game. I must say it was also pretty original, I did not expect to play anything like this during the jam. Nothing much to complain about, nice game for short sessions of few minutes to kill some time :)