Theater Calculators
Subwoofer Room Gain Estimator
https://www.theatersizing.com/calculators/subwoofer-room-gain/
Estimate only — not a calibrated SPL meter, an acoustic report or an electrical design. Confirm with measurement.
Subwoofer Room Gain Estimator
Small rooms boost deep bass. This is a coarse 10 log10(30/V) plus 3 dB per boundary (floor, wall, second wall), not a transfer-function.
Inputs
Results
- Volume
- 55.0m³
- Room gain
- 3.4dB
- In-room SPL
- 93.4dB
Calculation method
Gain ≈ 10 log10(30/V) + 3 × boundaries, then add to anechoic SPL.
Exact formula
G = 10 log10(30/V) + 3N. Limits: sealed-ish rooms, no leaky openings, no modal peaks on top of cabin gain.
Frequently asked questions
Is 30 m³ magic?
It is a reference living-room volume for this estimator, not physics scripture.
Corner loading?
That is the 3-boundary case. Gain is high; smoothness is not.
Open plan?
Treat volume as the connected space. Gain drops.
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