Output distance from a group of DR's

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DJ Scotty G
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Output distance from a group of DR's

#1 Post by DJ Scotty G » Thu Oct 12, 2006 9:29 pm

Hello, I have a question about output from a group of DR200's. they will be stacked vertical, 6 boxes total, 2 stacks of 2 cross-firing and 1 flat baffle. The bottom box in each stack will be about 6' off the floor. Any idea of the distance they would be able to have good sound level out to??


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#2 Post by Bill Fitzmaurice » Fri Oct 13, 2006 7:37 am

Use your SPL charts to figure it out. The chart shows output from one box. For every doubling of boxes add 6dB. Then for 100 watts system power add 20dB to the base SPL. For 1000 watts add 30 dB. That's a 1 meter figure. For every doubling of distance from the stack deduct 6dB. That's a minimum figure, which improves as a function of line height according to a formula too complicated to be concerned with.

This formula applies to all speakers.