I have a box already built it is 2.4 cubic feet and has a cutout for a 12 inch sub it has two 2.5 inch circles for ports how long should i make my tubes
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I have a box already built it is 2.4 cubic feet and has a cutout for a 12 inch sub it has two 2.5 inch circles for ports how long should i make my tubes
The sub and ports take up space in the box, so a 2.4 cubic foot box won't be 2.4cuft when the stuff is installed.
To know what port size you need, we need to know what kind of sub you're going with (the Thiele-Small parameters), and what frequency you want it tuned to.
51, 53, 116 on right-hand side might help you.
http://www.bcae1.com
The longer the length of the individual port tubes , the lower the frequency
What is fs of sub you will be using ?
Your port tubes may have bends to accomodate desired frequency of tuning.
WINISD , bassbox , et cetera [ enclosure design programs ]
I listen mostly to rap so it probably needs to be tuned arond 35
Vd [ft3] 0.0198 Hvc [mm] 31.6 Sd [m2] 0.052 Hvc [In] 1.24 Sd [ft2] 0.56 VC.Diameter [mm] 48 Revc [O] dual 2,9 Eff [%] 0.23 Levc [mH] (2000Hz) 4,85 (8 Ω) / 1,23 (2 Ω) S.P.L. [dB] 95 Xmax [mm] 10.8 R.M.S.Power [W] 400 Xmax [in] 0.4 M.M.P. [W] 1400 Zmax [O] 74,19 (8 Ω) / 18,6 (2 Ω) Sp. Displacement [l] 1.67 Nom. Dia.(In) 30 BI [Tm] 16,2 (8 Ω) / 8,2 (2 Ω) Sp. Displacement [ft3] 0.059 Qts 1.05 Rms[Ns/m] 3.39 Qms 13.79 Mms [g] 166 Qes 1.02 Cms [m/N] 7,6 x 10-5 F0 (in Cabinet) 55.8 Fs [Hz] 43 Mg.Wt.[g] 2100 Q0 (in Cabinet) 1.25 Vas [l] 32.7 Flux Density [Gauss] 7381 Vas [ft3] 1.15 Hag [mm] 10 Vd [l] 0.56 Hag [In] 0.39
https://www.stevemeadedesigns.com/bo...ng-fs-and-qts/
2nd post [ NDmustang65 ] . With a very high Qts (1.05) sealed box just screams at you.
http://www.ecoustics.com/electronics...io/214770.html
Fmods @ parts express are mechanical/electrical sub sonic filters.
http://www.google.com/shopping/produ...Lw_wcB#sgro=om this sub has a 28 Hz Fs and is 4 ohm. The power of your ZA amp .will work well.
http://www.jlaudio.com/12w3v3-4-car-...-drivers-92154
We are talking a low Fs = 26 Hz and we get the 500 bridged watts. :snap:
According to WinISD, tuned to 35hz and each port lengths of 8-3/16" would give you a 6db hump around 60hz
Attachment 6313
Tuned to 40hz with ports of 1-7/8 would give you a 7.5 db gain at 58hz
Attachment 6314
Did you figure any boxes with 2 1/2 inch ports ? Port "chuffing" being my concern.
http://www.rockler.com/2-1-2-clear-p...AaAh2REALw_wcB
Possibility of pipe for ports ^^^^^^^^^^4
Dsaulen0902,
Getting it sorted ?
Or , hopelessly confused ?
BOTH of them are configured with 2-1/2" ports...or more specifically, 2.68" ports, which is the closest size that appears in the drop-down menu of the program. The program also takes chuffing into consideration, and the highest of them shows a vent mach of .15, which is the upper limit. (yet is why the result is green and not red)
Awesome job , Al. !