Amplifier Power to SPL
SPL at the listener from sensitivity, power, and distance, with headroom and inverse power.
Example
You enter
- Speaker sensitivity (dB @ 1 W / 1 m) 90
- Amplifier power per channel (W) 100
- Distance m 1
You get
- Continuous SPL at listener 110 dB
Checked against published worked examples from: QSC.
Details, formula, and sources
Formula or tableSPL(d) = sensitivity + 10*log10(P) - 20*log10(d / 1 m); peak = SPL + crest factor; inverse power P = 10^((target - sensitivity + 20*log10(d)) / 10).
Source and editionFirst-principles loudspeaker SPL from the 1 W / 1 m sensitivity reference, the 10*log power term, and the inverse-square distance term (public; ANSI S1.1 decibel basis), by name.
Free accessPublic first-principles acoustics. A free-field estimate; the manufacturer's max-SPL spec governs.
What governsEstimate. AHJ and licensed professional govern.
API field namessensitivity_db, power_w, distance_m, spl_db
- Free field no room gain or boundary reinforcement modeledmethod