dB SPL:				Comment:
130	╶		╴	pain threshold
		|
120	╶		╴	peak hearing level
		|
103	╶		╴	peak music level
		|		↕ 20 dB crest factor
83	╶		╴	nominal music level
		|		↕53 dB signal-to-noise ratio
30	╶		╴	example background noise
		|
0	╶		╴	hearing threshold