Sound Attenuation Calculation

[shaunnutley]

I'm trying to work out how much I can hear through a thin external wall in a house and an extra 75ft beyond this wall. I believe that I would not be able to hear 50dB from 75ft away in a straight line using real ear attenuation (what I can hear). I consider 50dB of a person's voice (regardless of pitch) to be the highest level I would not be able to hear. I then estimate that the wall provides 50dB of sound reduction. The point is would I be correct in dividing the whole attenuation into two by adding the 50 decibels of the distance and wall together and assuming 100dB attenuation? Hence, would I be measuring this wrongly? To me it seems to make perfect sense.

[mibn2cweus]

Be advised this is not an expert opinion however that sounds like a reasonable assertion to me although a wall would not typically represent an ideal attenuator due to anomalies such as resonances and at higher SPL's the sound getting through would not retain its original qualities. Otherwise a 50db attenuator is a 50db attenuator.

[mibn2cweus]

I imagine you would also have to take into account that the wall is neither a point source receiver nor a point source transmitter in factoring in attenuation as a function of distance.

Sorry I can't help you more with this.

[mibn2cweus]

STC