SPL at distance
Sensitivity + amp power + distance → SPL at the listener, point or line source.
Free-field SPL at the listener. Enter the datasheet sensitivity (dB @ 1 W @ 1 m), the continuous watts delivered, and the distance. Point sources lose 6 dB per doubling; a column or line array inside its near field loses 3 dB. Upper bound only — rooms add reverberant gain and obstruction loss.
Free-field upper bound — what you'd measure outdoors on a windless day. Real rooms add reverberant gain and obstruction loss. Use it as a sanity check, not a spec.
Line source applies inside a column's or line array's near field only (roughly d < L² · f / 2c, where L is the array length). Past that it behaves as a point source again — check both and take the lower number if you're unsure.