Polys revisited

Polys revisited

Posted by emailtim (A) on September 19, 2023 at 19:41:06

Polys are usually installed vertically with a horizontal dispersion pattern as depicted below. This can cause uneven distributions and unwanted focal point concentrations.

I have resolved some side and cross side reflection issues I had by replacing my 1st reflection broadband traps with same-size horizontally mounted polys with 180 degree vertical dispersion design.

Any strong side-wall and cross side-wall reflections (within the designed frequency range) are redirected in a vertical fan pattern which attenuates the signal arriving at the ear. The re-directed energy is still in the room but now has a longer path to the ears so things do not sound as dead and the attenuated arrival time is delayed further from the direct signal.

Since it is mounted horizontally, it could extend the entire length of the sidewalls without incurring any of the issues associated with arrays of vertical mounted polys. It essentially creates non-parallel sidewalls.

There are online poly/radius/cord calculators that can be used to design various sized polys with desired dispersion ranges.

In short, the solid surface poly worked better than an OC-703 based broadband panel for those 1st reflections (as verified by REW sweeps in the sensitive [1-7]kHz range).

Line Source / Poly Ripple Tank Simulation:

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2022/03/30 Historical Records CENSORED

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Topic - Polys revisited - emailtim 19:41:06 09/19/23 (24)

One wonders if the sound have more air if the panels were removed. Nt - geoffkait 04:14:19 09/27/23 (4)

RE: One wonders if the sound have more air if the panels were removed. Nt - emailtim 08:05:12 09/28/23 (3)

RE: One wonders if the sound have more air if the panels were removed. Nt - geoffkait 09:51:26 09/28/23 (2)

Didn't you just say you used an SPL to measure room nodes ? - emailtim 14:16:23 09/28/23 (1)

Yes, I use an SPL meter to map out the room. - geoffkait 10:07:58 10/05/23 (0)

Plants are not good for the sound. - geoffkait 04:28:01 09/23/23 (11)

RE: Plants are not good for the sound. - Scholl 05:20:21 09/24/23 (6)

RE: Plants are not good for the sound. - geoffkait 07:54:13 09/24/23 (5)

RE: Plants are not good for the sound. - Tre' 17:55:43 09/26/23 (4)

RE: Plants are not good for the sound. - emailtim 08:21:11 09/28/23 (2)

must be he has a magic nasty plant too - Story 08:42:23 09/28/23 (1)

RE: must be he has a magic nasty plant too - emailtim 09:20:10 09/28/23 (0)

The only thing to fear is fear itself. - geoffkait 03:01:44 09/27/23 (0)

Those are not plants - emailtim 11:16:44 09/23/23 (3)

The Carpenters and the Beatles? Yup, that's Japan. Nt - geoffkait 12:27:17 09/23/23 (2)

Do your really think that this is the best place to air your prejudices? Nt - Tre' 17:37:15 09/23/23 (1)

You're right - geoffkait 03:15:45 09/27/23 (0)

Looks Very Interesting - Barry 13:12:35 09/21/23 (6)

RE: Looks Very Interesting - emailtim 15:25:31 09/21/23 (5)

RE: Looks Very Interesting - Barry 09:26:35 09/22/23 (4)

Mounting orientation - emailtim 11:24:00 09/22/23 (0)

RE: Looks Very Interesting - emailtim 10:36:06 09/22/23 (2)

Thanks so much! - Barry 15:26:54 09/22/23 (1)

REW Early Bird Release - emailtim 15:38:11 09/22/23 (0)

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