Phoenix Gold Phorum

here the thing I have a older 15" jl w0-4ohm sub
I also have a velodyme home sub amp
I put out 125w rms At 4 ohm
what size of box would you make
this is for my Theater Room so just for games and movies
the room size is 11ft x18ft
jl spec size is 2.5 sealed
spec on the sub
Free Air Resonance (Fs):19.2 Hz
Electrical “Q” (Qes):0.403
Mechanical “Q” (Qms):11.29
Total Speaker “Q” (Qts):0.389
Equiv. Compliance (Vas):12.63 ft3 357.8 litres
One-way, Linear Excursion 8.6 mm
Efficiency (1W/1m)**:89.8 dB
Effective Piston Area (Sd):130.2 in2, 0.0840 m2
Nominal Impedance 4Ω
Power Handling (continuous) 150W
Mounting Depth:7 in
Driver Displacement:0.110 ft3

what size would you make sealed and or ported
I would like sealed better
the sub is in a small 1.75 cub sealed box from my car years ago
but it is so loud as is...
I want to make something that will look good and sound great
info please

Personally, I would go vented. You can get a much better freq response with that sub. it will have a sharper fall off, but it will play lower. Just some basic specs in winISD confirmed this. You may want to play around with it to try and get a flatter response. i personally like a little lift in the low end for my movies. Also, you can get away with a much larger box in home theater applications. I had a xenon in a 5 cube box and it was really loud.

^^ Very true

What size port were you running that made the chuffing audible? Perhaps simply using a very large port is the solution for you.

This sub doesn't lend itself to play very deep vented without requiring a very large box. Best off sealed. Unless you have somewhere in the neighborhood of 12 cu ft of space to take up.