PSI to Loudness Calculator

dB vs tank pressure · DJD-anchored

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Horn model

150PSI

Drops as the tank empties — use your real cut-in PSI for worst-case

40200

Estimated horn output

148dB

Threshold of physical damage.

At rated pressure — full volume.

Pressure → loudness curve

16015014013012050 PSI100 PSI150 PSI200 PSI148 dBchord breaks down

The curve follows SPL ∝ 10·log₁₀(P/P_rated). Below 80 PSI the chord can't stabilize and output drops fast. Above 150 PSI you get diminishing returns — nozzles saturate and +50 PSI only adds ~1 dB.

Reference points for this horn

60 PSI
83.3 dB
80 PSI
145.3 dB
100 PSI
146.2 dB
120 PSI
147 dB
150 PSI
148 dB
180 PSI
148.8 dB

SPL is a logarithmic scale — 3 dB means double the sound intensity, 10 dB means roughly double perceived loudness. Dropping from 150 to 100 PSI costs about 1.8 dB, which you can hear but is small. Dropping below the chord threshold costs 10+ dB and the horn sounds completely different.