Hmm, not what I expected.

[thevic24 5,000+ posts]

ok, i have 28" of port area @ 27.5" long. thats somewhere between 35-37 hz.

if you go with 26" of port( the min you should go imo) then it would need to be about 25" long for the same tuning.

the first box that i built for my 3510 had 26" of port and had slight port noise at the tuning fq at hi volume. the box with 28" of port had 0 port noise at any power and excursion level.

 

[Slo_Ride 5,000+ posts]

thats a tough car to fit a box in. with the added port area it should be rather sick even with the power you have.i will go measure how long my port is and let you know.(mine is tuned to 36-37hz)

sorry had to get some grub. yeah tell me about it, very small car.

 

[Slo_Ride 5,000+ posts]

which way are you facing sub/port?

sub will be inverted facing towrds the windshield in between the seats

 

[thevic24 5,000+ posts]

sorry had to get some grub. yeah tell me about it, very small car.

mans gotta eat

see my post above for the port area and lengths.

 

[Slo_Ride 5,000+ posts]

ok, i have 28" of port area @ 27.5" long. thats somewhere between 35-37 hz.if you go with 26" of port( the min you should go imo) then it would need to be about 25" long for the same tuning.

the first box that i built for my 3510 had 26" of port and had slight port noise at the tuning fq at hi volume. the box with 28" of port had 0 port noise at any power and excursion level.

i'll try to go with 28 then

 

[Slo_Ride 5,000+ posts]

im glad u chimed in, otherwise who knows how long it would of taken me to get it straight

 

[thevic24 5,000+ posts]

im glad u chimed in, otherwise who knows how long it would of taken me to get it straight

any time bro. the 26" of port will sound good to but you may have a little port noise at high volume levels at the tuning fq but it shouldnt be that bad.

if you have the extra space then go with 28" for shure.

 

[Slo_Ride 5,000+ posts]

dont have a whole lot of spare time but as soon as i get it built I'll get it posted up. thanks to all for the help.

 

[thevic24 5,000+ posts]

dont have a whole lot of spare time but as soon as i get it built I'll get it posted up. thanks to all for the help.

good deal, shoot me a pm when you get going as i may miss the thread.

good luck, it seems you have your hands full.

 

[7ender 10+ year member]

I wouldn't be surprised if your problem is due to sub placement. Your box design isn't that bad. 4" port is not great, but it definetely wouldnt' be small enough to create any major problems that you're experience.

Iv'e faced my sub forward and experienced MAJOR loss in spl.

 

[Slo_Ride 5,000+ posts]

this box was first placed sub up, then i tried sub forward. it was louder sub forward.

 

[thevic24 5,000+ posts]

I wouldn't be surprised if your problem is due to sub placement. Your box design isn't that bad. 4" port is not great, but it definetely wouldnt' be small enough to create any major problems that you're experience.
Iv'e faced my sub forward and experienced MAJOR loss in spl.

a 4" port is no where near enough port area for his sub. that sub needs at least 16" of port per cube to work the way its design to.

 

[Cameron_B 10+ year member]

a 4" port is no where near enough port area for his sub. that sub needs at least 16" of port per cube to work the way its design to.

I think everyone has made it clear in this thread that he needs more port...

however...

What is trying to be said is that even though not optimal, a 1.5 cube box with a 4" port is NOT going to hinder the sub enough that a rf on 400watts is going to "blow it out of the water"

Ive ran many setups with limited port space.

ex 1.2 cubes single 3" 1.0 cubes single 3" etc

and while yes I did experience noise, and yes I did lose output, it was not a 10x increase in SPL

That sub should STILL be creating a good ammount of pressure in THAT box off THAT power.....unless you have another problem...

 

[snoopdan 5,000+ posts]

pics of gf?

 

[Decaf 10+ year member]

i bet the lpf is at 50hz and subsonic at 50hz

lulz

what headunit are u using

do u know what ur voltage drop is like... a 400w is easy for almost any car, 1200 is a different story