Hi everyone, I am looking for some input on a sub enclosure for my theater. I like the idea of making the front stage area an actual sub enclosure. The only issue I have is that I have to keep it relatively shallow, (20") so I can't port it from the front. I have over 8 feet of length, so I started putting together a design that would have 2 - RL-p15's in a dual ported configuration, with the ports on either end of the sub, extending into the lower units in my front columns.
Here's a rough MSpaint design, just to give you an idea about what I have in mind, these are very rough dimensions that don't include the thickness of the MDF, just the external dimensions:
I am unsure if having the ports exhaust into the lower units will be ok or if it will cause problems.
I ran some WinISD models, although I must admit I have no idea if I'm doing it properly, and this is what I came up with:
Driver : RL-p15
Project by : Erik Eastman
Project for : you
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Number of drivers : 2
Box type : Vented
Box size : 645.0 l
Tuning frequency : 12.00 Hz
Vent : 2 vent(s)
0.874 m length for each
0.140 m round
Relative
Freq Gain SPL
[Hz] [dB] [dB]
20.00 -8.09 84.35
25.00 -7.01 85.43
30.00 -6.00 86.44
35.00 -5.14 87.30
40.00 -4.43 88.01
45.00 -3.84 88.60
50.00 -3.35 89.09
55.00 -2.94 89.50
60.00 -2.59 89.85
65.00 -2.30 90.14
70.00 -2.05 90.39
75.00 -1.84 90.60
80.00 -1.66 90.78
85.00 -1.50 90.94
90.00 -1.36 91.08
95.00 -1.24 91.20
100.00 -1.13 91.31
I have no idea if this is acceptable or if I am even on the right track or not. I figured out the cubic meters inside the enclosure, converted to liters, subtracted 25% for driver, bracing, and stuffing volume, and came up with 645liters +/-. This seems to be pretty good.
Would it make more sense to tune it higher to shorten my port length, so I could fit 4 15" across the front instead?
If anyone can help me I would greatly appreciate it, I am constructing my room and I need to know what direction to go before I build my front stage.
Thanks,
Erik