Q: studies of how hair / earpiercings do (/don't) affect hearing? Options

[Porcus]

Links / sources, anyone? I'm curious, and a web search only led me to numerous discussions (typically uneducated ones) on whether the nerves could be damaged by a tragus piercing, and not anything on e.g. how big jewelry must be in order to be 'earplug'-alike distortion.

_{(And no, I won't be seen dead with a combover. Find another lab rat.)}