By PSW Staff • October 27, 2010 This calculation will give you the amount of attenuation, in decibels, you can expect with a change in receiver distance, in a free field (outdoors). For example if you were standing 20 feet from a loudspeaker, and were to move to 40 feet away from that loudspeaker, you would expect to see a drop in level of 6 dB. Sound that is radiated from a point source drops in level at 6 dB per doubling of distance. Equation used to calculate the data: Snew=Sref + (20 * Log (Dref / Dnew) Where: Dref = Reference Distance Dnew = New Distance Sref = Reference Sound Level Snew = New Sound Level Comments Have something to say about this PSW content? Leave a comment! Cancel reply Scroll past the ”Post Comment” button below to view any existing comments. Your email address will not be published. Required fields are marked *Comment Name * Email * Website This site uses Akismet to reduce spam. Learn how your comment data is processed. Tagged with: Amplifier World Audio Crown Engineer Live Sound Reinforcement · all topics Subscribe to Live Sound International Subscribe to Live Sound International magazine. Stay up-to-date, get the latest pro audio news, products and resources each month with Live Sound.