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Old 14th December 2011, 11:51 PM   #81
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Rather than bells it's sometimes easier to visualize pushing a child on a swing. You don't actually need to push continually, just time a light tap properly. And any taps *not* properly timed mess the whole thing up. But *all* taps make the swing move some.

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Old 14th December 2011, 11:56 PM   #82
Pano is offline Pano  United States
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Sure, but with the reduced power available in the noise at the needed resonance, the bell may ring and the swing may swing, you just won't notice it.
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Old 15th December 2011, 12:01 AM   #83
dewardh is offline dewardh  United States
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"extremely flat response over a broad frequency range . . . ideal for use in . . . sound absorption . . . measurements"

Could we get back to a low cost DIY version, please?
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Old 15th December 2011, 12:05 AM   #84
dewardh is offline dewardh  United States
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Quote:
Originally Posted by Pano View Post
the bell may ring and the swing may swing
Not if the taps are random (like noise) . . . sometimes you reinforce the swinging, sometimes you cancel it. It averages out to lots of pokes in the back for not much fun . . .
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Old 15th December 2011, 12:06 AM   #85
RevMen is offline RevMen  United States
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Actually I'd really like to hear why pink noise can't be broken down into component sines and cosines. It's very relevant to the general discussion, and if my understanding is incorrect, I'd like to correct it sooner rather than later.

Last edited by RevMen; 15th December 2011 at 12:11 AM.
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Old 15th December 2011, 01:07 AM   #86
dewardh is offline dewardh  United States
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Actually I'd really like to hear why pink noise can't be broken down into component sines and cosines.
I suspect that you are confusing "sines and cosines" as mathematical functions with continuous waves. Not the same . . .
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Old 15th December 2011, 01:22 AM   #87
Ron E is offline Ron E  United States
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Originally Posted by RevMen View Post
Actually I'd really like to hear why pink noise can't be broken down into component sines and cosines.
It is not periodic.
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Old 15th December 2011, 02:18 AM   #88
Ron E is offline Ron E  United States
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Could we get back to a low cost DIY version, please?
6 of these on a cube Put a 1/4"-20 insert on one corner of the cube and put it on a tripod. Feed it with MLS and measure
Aurasound NS525-255-8A 5.25" Paper Cone 8 Ohm: Madisound Speaker Store
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Last edited by Ron E; 15th December 2011 at 02:22 AM.
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Old 15th December 2011, 02:57 AM   #89
dewardh is offline dewardh  United States
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6 of these on a cube
Nasty response curve, and definitely beaming even with six of them. NSW2 on a pipe works better, flatter and still omni to well above 2kHz (pretty good at 3, even 4k). Already have, and have tried, that. Might work up to over 5k with more of them (but expensive). Getting smooth and omni from a cone or dome above 4k is difficult. The 100-10,000 range of a fan (if they really can do that), and the absense of peaks and dips, is pretty attractive. I have a shelf full of drivers that I'd try before the 5" Aura . . .
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Old 15th December 2011, 03:26 AM   #90
RevMen is offline RevMen  United States
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I suspect that you are confusing "sines and cosines" as mathematical functions with continuous waves. Not the same . . .
Do go on. I'm riveted.
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