# Find Displacement Amplitude for 79.8dB Wave

The highest note written for a singer in a published score was F-sharp above high C, 1.48 kHz, for Zerbinetta in the original version of Richard Strauss's opera Ariadne auf Naxos.
The wavelength of this wave is 0.232m.
Suppose people in the fourth row of seats hear this note with level 79.8 dB. Find the displacement amplitude of the sound.

A=Δpo/ωρc
f=v/λ
ω=2∏f

By substituting all the known values into the first equation I'm left with an unknown variable - Δpo.

I've looked everywhere to try and discover an equation for the pressure amplitude but to no avail. I'm assuming it has something to do with the loudness I've been given but I've been plugging away for an hour or so now and I've come nowhere near a correct answer.