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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: tkroeker on September 30, 2016, 01:42:19 PM
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So one piece I'm missing is this.
when two speakers couple, is it at Hz above or below the 1/2 wavelength?
i.e. ( roughly)
two 18's
80 Hz = 14 feet
1/2 wavelength = 7 feet
if the two 18's are under 7 feet apart will they couple 80 to 500,, or 80 down
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So one piece I'm missing is this.
when two speakers couple, is it at Hz above or below the 1/2 wavelength?
i.e. ( roughly)
two 18's
80 Hz = 14 feet
1/2 wavelength = 7 feet
if the two 18's are under 7 feet apart will they couple 80 to 500,, or 80 down
They stop canceling and begin to couple at frequencies whose 1/4 wavelength is larger than the driver spacing. You get summation over a 1/2 wavelength range, but it is plus/minus 1/4 wave around zero phase offset. Since there is no minus offset involved in driver spacing it is only 1/4 wavelength, a 1/4 wavelength being 90º of phase offset.
Mac
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if the two 18's are under 7 feet apart will they couple 80 to 500,, or 80 down
They couple as the freq goes LOWER.
The spacing is the UPPER limit.
Because as the freq goes lower, the wavelengths get longer, so they get "acoustically closer" as the freq goes down.
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They couple as the freq goes LOWER.
The spacing is the UPPER limit.
Because as the freq goes lower, the wavelengths get longer, so they get "acoustically closer" as the freq goes down.
awesome thanks