Sound level at distance
Source SPL + distance → level drop by inverse-square law
Input
SPL at distance
at 1 m: 115 дБ
95 дБ
- SPL @ 1м
- 115 дБ
- @ 10м
- 95 дБ
- Peak (+3dB headroom)
- 118 дБ
In free field −6 dB per distance doubling. SPL = sensitivity + 10·log10(W) − 20·log10(m). For 100 dB concert level at 10 m you need ~120 dB at 1 m.