Can some please calculate the weight of polyfill required to get rid of internal standing waves of a 2.16lt sealed enclosure. Or is there a chart recommending the amount of polyfill in weight for enclosures of different sizes.
Box internal dimensions
Height:214mm Width:82mm Depth:132mm
1st mode standing wave wavelengths
Height Width Depth
801 Hz 2.09 KHz 1.30 KHz
PS: Since the box has been downsized from 11.5lt to 2.16lt, not sweating of the effect on Qtc.
Box internal dimensions
Height:214mm Width:82mm Depth:132mm
1st mode standing wave wavelengths
Height Width Depth
801 Hz 2.09 KHz 1.30 KHz
PS: Since the box has been downsized from 11.5lt to 2.16lt, not sweating of the effect on Qtc.
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You want at least 1/10th, preferably 1/4, of a wavelength, to get substantial absorption.
1 wavelength at 800Hz is 17 inches. So 1.7" to 4" of fluff. On each side. 3.4" to 8" total.
Your box runs 5" average side. So basically "all the space". At least half of each dimension, three ways.
But this box is not the room your ears are in. Internal modes are significantly attenuated to get through speaker cone. You do not need to "get rid of" standing waves (anyway you can't). Just reduce them. Any fuzz is better than none; lots more fuzz is not much difference.
And 2 liters is not a lot of fuzz. Go through your sock drawer and pull out the worn-heel socks, that will do.
1 wavelength at 800Hz is 17 inches. So 1.7" to 4" of fluff. On each side. 3.4" to 8" total.
Your box runs 5" average side. So basically "all the space". At least half of each dimension, three ways.
But this box is not the room your ears are in. Internal modes are significantly attenuated to get through speaker cone. You do not need to "get rid of" standing waves (anyway you can't). Just reduce them. Any fuzz is better than none; lots more fuzz is not much difference.
And 2 liters is not a lot of fuzz. Go through your sock drawer and pull out the worn-heel socks, that will do.
When you say fuzz, do you mean polyfill? If so, then since I'm getting 2 kg of polyfill to stuff the sealed subwoofer I'm building I'll have a lot of it to use in the 2.16 ltr main speakers.
Is it not possible to attenuate box standing waves with polyfill in a 2.16 ltr box so that it does not show on the FR and impedance curve when measured. Do I need to use something thicker like socks as you mentioned?
Is it not possible to attenuate box standing waves with polyfill in a 2.16 ltr box so that it does not show on the FR and impedance curve when measured. Do I need to use something thicker like socks as you mentioned?