Always careful with volume levels, and despite a life of playing in bands and running FOH ("fulltime job" for both), a head-on motorcycle accident with me spearing the windshield of the car that crossed the double-yellow into my path (60mph vs 65mph) has provided for a lovely symphony of high(er) pitched tones. At any given time, always at least one frequency screaming, up to three additional frequencies layered now and then. Blood pressure and sinus health have a huge impact.