Sound level meter - Frequently Asked Questions

Output voltage when the bar indicator is at its upper limit: UPPER_V

dB change rate per 1V: FACTOR (dB/V)

Output voltage: Assuming DC

Sound level (dB) = FACTOR x (DC - UPPER_V) + UPPER_dB

example

Level range display upper limit UPPER_dB = 90 dB

Output voltage at the upper limit of the level range: UPPER_V = 2.5 V

When the voltage is 0.25 V at 10 dB, the dB change factor is 40 dB.

When the DC output voltage is 1.0 V,

Sound level (dB) = 40 x (1.0 - 2.5) + 90 = 30 dB