> >and the yoga block I attached them as "cheeks" on each side of the
> >block.
> Not sure what you're describing exactly, but as long as the boundary
> planes are unobstructed it, should be fine.
I'll post some pictures and audio later today. Not many places open
around us due to hunting season. Will try one of the parks near us.
> Using closed-cell high density foam as a boundary tends to
> concentrate more of the boundary effect lift in the 1K-3K Hz range at
> the expense of 400-1K Hz and 3-6 K Hz response. Comments on Vicki
> Powys last pink noise test in the DIY Boundary Mics blog outlines
> some of this. Its not a huge deal, but you might want to try finished
> wood or another harder boundary material in your next experiment.
The boundaries are wood. I guess I should've described it better. :)
It's built per the plan, some fudges here and there. The angle is
listed as 35 degrees and yet a 35 degree cut didn't meet the boundary
length of 3 5/8" with a 4 1/2" opening between the boundaries, oddly
enough a 45 degree angle worked exactly and left the mics angled at
roughly 110 degrees. Typo?
> >Now I just have to fill the voids in the back and we're set. Has
> >anyone used "Great Stuff"? Or does it need to be a denser material?
> The low expansion formula for doors and window will work and is
> easier to control. Maybe put a piece of wax paper so it doesn't fuse
> to the foam baffle? You just need to close-up the open area but it
> doesn't have to be air-tight.
Heh, good idea. I will do that when I have a chance. For now I stuck a
couple old socks in there (clean socks!). :-)
> There are lots of people to thank, actually, including Michael
> Billlingsley, Bruce Bartlett, Crown International, Walter Knapp and
> Lang Elliot and Mike Rooke. Vicki Powys has also utilized SASS-P
> dimensions in her array using two 172's per side that's impressive.
> I'll be posting a comparison with her SASS-P MKH-20 mod on the DIY
> Boundary Mics blog in a short while. Rob D.
I stand corrected, credit where credit is due. Thanks everyone!
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