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Fyi,
Using the Barker code, panel size of 93.5cm, 4.25 well-segment, for anyone with a 500cm wall, it's possible using N11^2 and N17^4. Just one needs to tack on a separate small frame of about 25.5cm, containing 6 wells, on the right side (or change frame sizes, see below).
Barker code
7 [-1 -1 -1 +1 +1 -1 +1]
-1 = N11 (4 periods)
+1 = N17 (3 periods)
N11 (constant +2) 811LF (405.5 eff. LF Hz)
N17 (constant + 4) 972LF (486 eff. LF Hz)
22 wells (4.25 well-segment) fit into a frame (23 possible with a small spacer).
Shift all N17 zero wells over by 3 places, making a zero-well at position 11.
PATTERN
N11 N11 N11 N17 N17 N11 N17 (can be reversed)
For 4 frames (+alpha):
F1 = N11+N11
F2 = N11+ first 11 wells of N17
F3 = last 6 wells of (F3) N17 + (F4) N17
[small spacer]
F4 = N11+ first 11 wells of N17
Fa = last 6 wells of N17 (25.5cm)
Imagine a 500cm wall, and in the corners you want a 60cm (2') sheet of 10cm/4" rockwool/fiberglass to straddle them. This means you need 43cm of each side of the 500cm wall for it (= 86cm from the 500cm used).
So max length for diffusion = 414cm.
The N11/N17 panels above = 403.75cm in length, giving +5cm (1") of play on either side -- in other words a perfect fit.
A perfect fit, perfect Barker code, standard (3') frames, plus alpha. An easier build than higher primes, in terms of measuring, though less resolution.
But if the Barker code is crucial, for the size needed, and with easier construction, if you don't mind spanning frames (and losing mix and match modularity). So, yet another solution.
If you wish to build 4 frames, 2 larger 4' frames, of different sizes, etc. (for a 16'6" wall or so). No position shifting is necessary, as all N-periods are self-contained in a frame:
F1 = N11 + N11 (93.5cm/3')
F2 = N11 + N17 (121cm/4')
F3 = N17 + N11 (121cm/4')
F4 = N17 (74cm/2'4"ish)
This seems to fit a North American 4' x 8' better than the cm sizes I get, where (93.5cm2) 3' x 3' works well.
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