Alot louder with door open, not enough port area?

[travicles 10+ year member]

Haha get used to it. I also have a regular cab truck, and the bass is so much louder with both windows open. It is unfortunate, I know.

 

[T3mpest 10+ year member]

Opening doors and windows allows the windows to function as ports.. The car itself adds ALOT to the bass.. Remember, most setups that do 150's in walls wouldn't do more than a 125 or 130 if you measured it in a empty field from the same distance away.. 30db's of gain, which is common due to cabin gain, is like adding 10,000 watts of power to speaker.. Really for a daily driver you can't do much to fix this phenomenon, just realize that it's all part of a much larger gain structure that is already working in your favor.

ss

 

[Phoenix Risen 10+ year member]

its just acoustics, if you really work with the vehicle you can find the way around it though.

 

[Mitch86 5,000+ posts]

My truck ***** sealed up to the point that its barely audible, but roll down a window and it rattles your eyes. (Depending on the set up) Not sure that you can really do anything about it either. I have had all kinds of set ups and all of them were the same way.

 

[mylows10 5,000+ posts]

it has to do with what the resonant frequency is of your truck the closer to that frequency the louder you'll be with the windows up,the farther from that frequency the lower you db's will be sealed.

 

[JoshC 10+ year member]

i gain 4-6 depending on the system im running, port area is part of it, but it also has a lot to do with the vehicle,
a tahoe that i meter looses a good 4db by when something is open. it just how things work,

and you are a good bit short on port area, i would say at the least add another 3", but it would probably be better to go with a pair of 4" or a single 6"... how much power?

Im considering going to 2 4in ports, it would be a pain to redo my box to a large slot port but maybe my dudes up to it. I have 1.2K on tap but my OA dosnt want more then 800 or so in that box. Both SPL audio and the guys at OA said the box was rather large. But my builder wanted a very low resident Fq for the box since i want my lows as loud as possible lol so it just dosnt take as much powa

Haha get used to it. I also have a regular cab truck, and the bass is so much louder with both windows open. It is unfortunate, I know.

No its opposite for me. My bass gets a bit better/deeper with windows down, but you open a door and it gains 3-5db(maybe more). Deff a good audible change, very noticeable to anyone in the car.

So after reading everything looks like it time to redo the box for more port and possibly take some space out. Thinking ill make the box 1.9-2cu^ft @ 30Hz with 2 4in aeros or a slot port. May just end up doing a whole new box, but if i decide to go that route ill probably switch to 2 10s

Lots of responses and good info, thanks guys. Ill be sure to post up a log of whatever i end up doing

EDIT: also considering going to a bigger 12, 1-1.5Krms area

 

[RangerDangerV2 5,000+ posts]

Im considering going to 2 4in ports, it would be a pain to redo my box to a large slot port but maybe my dudes up to it. I have 1.2K on tap but my OA dosnt want more then 800 or so in that box. Both SPL audio and the guys at OA said the box was rather large. But my builder wanted a very low resident Fq for the box since i want my lows as loud as possible lol so it just dosnt take as much powa

No its opposite for me. My bass gets a bit better/deeper with windows down, but you open a door and it gains 3-5db(maybe more). Deff a good audible change, very noticeable to anyone in the car.

So after reading everything looks like it time to redo the box for more port and possibly take some space out. Thinking ill make the box 1.9-2cu^ft @ 30Hz with 2 4in aeros or a slot port. May just end up doing a whole new box, but if i decide to go that route ill probably switch to 2 10s

Lots of responses and good info, thanks guys. Ill be sure to post up a log of whatever i end up doing

EDIT: also considering going to a bigger 12, 1-1.5Krms area

go with a slot port, you want to try to keep the cabin pressure down...

 

[supermaxx123 10+ year member]

I've never actually tried playing my system with the doors open and me inside. Reg cab truck so the space is tiny but so is my box!. For 2.2 cubes 2 3" port ports won't cut it imo. I'm running 12"^2 of port in .7cu/ft. I get no port noise and tuned to 37hz my bottom end bottoms out at 28hz

 

[The_Grimy_One 10+ year member]

your probably right man, like i said my iphone calculator ***** because i cant use parenthesis.

WHAT iPhone do you have???

 

[Blue Fury 10+ year member]

go with a slot port, you want to try to keep the cabin pressure down...

What? How would a slot port help keep the pressure down vs an aero port? And isn't his goal about increasing the SPL with the doors shut.. not decreasing it?

Don't just switch out your ports for something you think will work. Who designed your box? Depending on the flare that the port has, you've got a very small window of what will work for what you want it tuned to. 14sqin for 2.2cft is on the low side. If you increase the area, you have to increase the length to maintain the tuning. If you increase the length but don't increase the box size, you decrease the net volume consequently requiring less port area. Then you have to iterate a few times to find the right area/length/volume combo. It's less headache to make a new box.

You say you want 2 4" aeros at 30hz from 2 3" aeros at 33hz. You're going to have a significantly bigger box even after the 0.3cft reduction. And if you're lowering the tuning, the probability is very high that you wont get the loudness you're looking for with the door shut since you're likely tuning away from your cabin gain freq. If you tuned upward, you'd get that loudness but skimp the

 

[RangerDangerV2 5,000+ posts]

What? How would a slot port help keep the pressure down vs an aero port? And isn't his goal about increasing the SPL with the doors shut.. not decreasing it?



Don't just switch out your ports for something you think will work. Who designed your box? Depending on the flare that the port has, you've got a very small window of what will work for what you want it tuned to. 14sqin for 2.2cft is on the low side. If you increase the area, you have to increase the length to maintain the tuning. If you increase the length but don't increase the box size, you decrease the net volume consequently requiring less port area. Then you have to iterate a few times to find the right area/length/volume combo. It's less headache to make a new box.

You say you want 2 4" aeros at 30hz from 2 3" aeros at 33hz. You're going to have a significantly bigger box even after the 0.3cft reduction. And if you're lowering the tuning, the probability is very high that you wont get the loudness you're looking for with the door shut since you're likely tuning away from your cabin gain freq. If you tuned upward, you'd get that loudness but skimp the

what I have been told is that aeros are really good for keeping cabin pressure up... in this case, the op doesnt want more cabin pressure because that is more pressure against the front wave of the cone... if he has less cabin pressure (open door) the subwoofer doesnt have to "work" as hard as it does sealed.. but I could be wrong.

 

[Blue Fury 10+ year member]

You're on the right track but in a nutshell it's like this. You open the door, the door is the new 'port' where the cabin is the enclosure. It was mentioned already. It's like increasing the order of the enclosure if you count the cabin as an enclosure in itself.

Idk who told you that about aeros, he might have been stoned. Aeros are for reducing turbulence with a byproduct of reducing actual port length by a minimal amount. Aeros, from reducing turbulence, have an effect of essentially increasing the port area by a minimal amount. That's why you see boxes with aero's with a smaller port area than those with non-aero.

 

[JoshC 10+ year member]

What? How would a slot port help keep the pressure down vs an aero port? And isn't his goal about increasing the SPL with the doors shut.. not decreasing it?



Don't just switch out your ports for something you think will work. Who designed your box? Depending on the flare that the port has, you've got a very small window of what will work for what you want it tuned to. 14sqin for 2.2cft is on the low side. If you increase the area, you have to increase the length to maintain the tuning. If you increase the length but don't increase the box size, you decrease the net volume consequently requiring less port area. Then you have to iterate a few times to find the right area/length/volume combo. It's less headache to make a new box.

You say you want 2 4" aeros at 30hz from 2 3" aeros at 33hz. You're going to have a significantly bigger box even after the 0.3cft reduction. And if you're lowering the tuning, the probability is very high that you wont get the loudness you're looking for with the door shut since you're likely tuning away from your cabin gain freq. If you tuned upward, you'd get that loudness but skimp the

Well i can open the box up to accommodate for larger ports but switching to slot would be a pain and not likely worth it. Honestly the options that wouldnt be to difficult to do is go 1in bigger on the ports. If thats not really a good option i might as well do 2 10s(get 500-600wrms a pop), or do you think i could do just as well with a 1-1.5k 12? I could just get a bigger 12 then do a new box or vice versa

 

[audiobaun 5,000+ posts]

I have found out as today, that my new box with the slot ports verses the aero ports seem to give me better sound,and fantastic pressure levels,and much better with the windows down at halfway, just on a pair atm,,its insane,and ive done seperate chambers this time, and to me sounds so much better..1 pair of 10s,tomorrow the other 2 will be up and running..Ive been concerned about the airbags in the dash, and the steering wheel already,hoping they do not release.My tens sound great, but i am in an xcab..I did do 4 svc tens in a single cab before,all in sealed boxes,and sounded fantastic,,were Kicker Stillwater,on a Hifonics VII Boltar,in a 87 Toyota truck

 

[Falcons 5,000+ posts]

WHAT iPhone do you have???

iPhone 4 lol. When I type in a=pi*r^2 it squares the whole thing. So if I had done it properly I would have had to square the radius then multiply by pi. It's not that complicated just annoying lol