SEALED vs PORTED (basic info.)

[squeak9798 5,000+ posts]

sorry to rephraze the question that i asked.... usually when a subwoofer is mounted the rear of the sub, the magnet is inside of the box. if the subwoofer is instead mounted with the magnet on the outside of the box with the cone facing the inside is the performance of the subwoofer changed? by performance i mean sq, and frequencies and power handling. are certain subs not even designed to be mounted this way? if so where can i find this information i already checked the manufacturer's website.

Performance is not changed. You can do it with any subwoofer.

Just keep in mind that it will have an effect on the box size, however.

 

[Beat_Dominator 5,000+ posts]

Also, keep in mind that the real world vented enclosure will tune lower than predicted. That Kicker when loaded in an enclosure and begins having real power touch its VC, the box tuning will fall to somewhere near 34-35 Hz.
When designing an enclosure for a super sub, say a Titanium or W7, you must design the box with tuning about 6-7 Hz higher than desired. If you ever modeled the 32 Hz tuned vented enclosure for the W7 on JL's website, you will see that it is tuned at 38 Hz.

Wondering what evidence you have for this? Seems like that defeats the purpose of tuning a box at all, unless you are talking about cabin gains?

 

[jimmyjames1700 10+ year member]

Wondering what evidence you have for this? Seems like that defeats the purpose of tuning a box at all, unless you are talking about cabin gains?

Follow the link below and check out the tuning freq of their own recommended 32Hz tuned box with. Mathematically it is designed to be tuned at around 38Hz.

http://www.jlaudio.com/subwoofers/pdfs/12W7_MAN.pdf

In fact all W7's, or other supersubs for that matter, need to be designed with box tuning that much higher (6-7Hz).

When we first started designing and building custom vented boxes for the W7's we wondered why the tuning always ended up way lower than predicted. In fact, the first 32Hz vented box we designed and built for a customers 12W7 ended being tuned at 26 Hz! It definitely perked my curiousity.

So a after a quick call to Hector at JL we learned that simple port formulas or programs like BassBox Pro cannot accurately predict what a sub/box combination will do once current starts flowing through a subs Voice Coil. Thats why the big shot's use programs like Leap which take into account many other factors. Basically T/S parameters and box calculators just get you into the ball park.

I've seen it first hand. All vented sub enclosures designed with port formulas our say BassBox Pro will tune lower than predicted. Most will tune about 10%-15% lower than predicted, with the supersubs usually being significantly more.

 

[singlesubsetup 10+ year member]

Humm, to bring a thread back to life, (yea i used the search button ) has completely made me rethink my considered box tuning.

The sub I have has an Fs of 39

Would building an inclosure with a tune of 38hz be appropriate?

 

[Decado 10+ year member]

when i do calculations do i have to get them into the same units? For example, for Vd i have to do Sd x Xmax, and with the info i have it is 13.35 mm for Sd and 467.59 cm squared for the Xmax, do i have to put these both into mm? or cm? or what?

 

[EddieB 10+ year member]

//content.invisioncic.com/y282845/emoticons/up2something.gif.dd110ecf3ae4b76050d87598f2f8de7c.gif Ok I've read these posts ! I listen to rap music and R&B Whats sounds better sealed or ported and will making a completely sealed box damage my subs two 12"JL audio?//content.invisioncic.com/y282845/emoticons/up2something.gif.dd110ecf3ae4b76050d87598f2f8de7c.gif

 

[squeak9798 5,000+ posts]

12" JL Audio tells us nothing. JL has had 25 different sub models over the years.

Anyways....for rap you will generally want ported, assuming your subs will perform well in a ported enclsoure.

 

[Serialk1llr 10+ year member]

Hey, JL Audio 12w3v2 D4

I've been reccomended to put it in a sealed box because I a) drive a scion tC (read cheap hatchback) with limited space, and b) listen to a _broad_ range of music. I believe JL reccomends 1-1.5 cu.ft for a sealed enclosure.

ANY comments?

 

[jalverson 10+ year member]

sounds good mang

 

[funJeep]

I want to build a bandpass box 4th order for a DUAL XiNC110 woofer. It maxes out at 600 watts and has a 50-150 watt RMS range...the frequency range for it is around 30hz-220hz i believe. What I need to know is what frequency to tune the box I wanna build for rock/hard rock sound. This right now is the only thing holding me back once I figure that out I can use a design program and figure out the dimensions it should be and everything else. The dimensions I'm hoping to use are 15"W,13.5"H,12"D so if I use those dimensions what could I do to tune my box to a flatter frequency? I made a thread in this forum a while earlier but I'm desperate for a solution quickly so I can get started ASAP so some help would definatly be appreciated. Thanks to anyone who does reply to this with some useful info

 

[SlammeD_SiR 10+ year member]

you guys make it seem like u wont have badass bass wit a sealed box????

i got a type x alpine n i dunno much about boxes but i was thinking of going sealed. wha u guys think

i listen to basically everything house techno dnb hiphop so i want it to be good overall

 

[bimma85 5,000+ posts]

you guys make it seem like u wont have badass bass wit a sealed box???? i got a type x alpine n i dunno much about boxes but i was thinking of going sealed. wha u guys think

i listen to basically everything house techno dnb hiphop so i want it to be good overall

No way port that bish. Night and day

 

[SlammeD_SiR 10+ year member]

y would u chose port tho??? personal pref??

No way port that bish. Night and day

 

[bimma85 5,000+ posts]

y would u chose port tho??? personal pref??

Sealed...output= shitty. 1.75 net tuned to 32 and she sounds awesome and get pretty dam loud

 

[SlammeD_SiR 10+ year member]

the only problem is everyone i heard wit a ported sounded loud but shitttyyyyyy.. im sure if u do it proper it would be good i just dun want my sub sounding like a fart lmao //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif :crazy:

Sealed...output= shitty. 1.75 net tuned to 32 and she sounds awesome and get pretty dam loud