waveforms, sound opens up an incredible world.
i got into it via short wave radio, built simple little notch and pass filters using IC's, op amps etc, all many years ago. The film 'The Conversation' had Gene Hackmann doing the same thing...... I beat him to it ! !
the maths was always way beyond my ability,but it leads into things like standing waves, both electrical and mechanical.
Base your life on what you know, have achieved, be careful of dreams ....