How much louder is the SPL in a ported box compared to a sealed

 

New member
Username: Creative

Newark, CA USA

Post Number: 2
Registered: Apr-05
I have two kicker comp vr 12" and I have them in a sealed 1.38 Cubic feet box running about 300 watts per sub. How much louded would the SPL be in a ported box then a sealed box?
 

Gold Member
Username: Insearchofbass

Post Number: 1446
Registered: Jun-04
on average 3 db louder
 

cuspid fo life
Unregistered guest
you smell
 

New member
Username: Creative

Newark, CA USA

Post Number: 3
Registered: Apr-05
How loud is 3db? Would people be able to hear me down the block with my sealed box?
 

Bronze Member
Username: Mixneffect

Orangevale, Ca. USA

Post Number: 54
Registered: Apr-05
Here is an example of the difference between a sealed box (red) and a ported box (yellow).Upload
 

Bronze Member
Username: Jbailey

Indianapolis, Indiana

Post Number: 54
Registered: Mar-05
Hey mixneffect, what is that program you're using for the box design and, if possible, where can I find it online? Thanks
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 7685
Registered: Dec-03
average for a daily driver going sealed to ported is +3dB which is roughly an increase in audible volume of around 33-50%
I've seen a ported enclosure tuned to ~60Hz and set up for SPL, that had a gain of something like +9dB which is tremendous. that's roughly double the volume perceived by your ears.

my suggestion for 12" Kicker CompVR subs is to go to a ported box with 2.0cu ft per sub after driver and port displacement. use 4"ID round ports or slot ports and tune the enclosure to 34Hz.
set your sub amp's subsonic filter to 20Hz and you should be good to go.
with two subs, you'll get roughly double toe output of your current sealed setup
 

Silver Member
Username: Suleman36

Post Number: 774
Registered: Feb-05
They glass the Avalanche 15 i have has a resonant freq of 15.7 Hz. What should i tune this thing to...i was thinking 22Hz-26Hz ?? Going in 3.5 cu ft.
 

Silver Member
Username: Suleman36

Post Number: 776
Registered: Feb-05
I listen to mostly rap and electronica and alittle nine inch nails. I wanna daily SQ/SPL driver that can be loud and accurate at the same time. So like since the resonant freq. is so low at 15.7Hz you think between 22Hz-26hz makes sense and its going in 3.5 cu ft.
 

New member
Username: Creative

Newark, CA USA

Post Number: 9
Registered: Apr-05
The guys at Stereo City said that for an Integra it's better to get sealed box because it's a hatch and sealed box subs sound the best. Are they right? Well I m stuck with my sealed box pretty much because I got it for so cheap from them. I have the Zapco I-2100 amp two channel amp. My two Kicker Comp VR is DVC and 2ohms. I was going to wire my two subs series/parellel then I found out that my amp isn't stable at 2ohms so now I have to switch out the subs to 4ohms. So could you help me tune the amp? Here are the specs of the amp:

Stereo, 4 ohms : 2 x 100 Watts
Stereo, 2 0hms: 2 x 175 Watts
Mono, 4 ohms: 1 x 350 Watts
600 Watts Total Music Power

T.H.D. : <0.3%
Frequency Response: 10 - 25KHz
S/N Ratio: >90dB
Channel Separation: >50dB
Dimensions: 13"L x 9.9"W x 2.25"H

2-Channel Amp with Crossover and Remote Bass
-Balanced line input for OEM integration
-Unbalanced RCA input
-RCA output
-Bridgeable 2-channel amp
- MOSFET power supply
- Bass equalization
-Variable electronic crossover
- Remote bass gain
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 3742
Registered: May-04
"The guys at Stereo City said that for an Integra it's better to get sealed box because it's a hatch and sealed box subs sound the best. Are they right?"
They're stereotyping. Ported boxes can sound just as good and better than sealed, but ONLY when done correctly. This necessitates a low tuning frequency, adequate box volume, and using as much port area as you can get in the space you have. If ported were inferior to sealed, then high end home audio systems wouldn't use them, and you'll see that more subs are ported than sealed in the home environment for a variety of reasons. In terms of transient response, group delay, and phase shifts, sealed wins, but in terms of output, low distortion, and total control of the subwoofer at and near resonance, ported wins. SQ is subjective, choose based on what you like the sound of. Your car will work well with either.
 

Silver Member
Username: Suleman36

Post Number: 782
Registered: Feb-05
the Avalanche 15 i have has a resonant freq of 15.7 Hz. What should i tune this thing to since the resonant freq. is so low...i was thinking 22Hz-25Hz ?? Going in 3.5 cu ft.
 

Silver Member
Username: Suleman36

Post Number: 788
Registered: Feb-05
?
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 3745
Registered: May-04
Didn't you already decide on 27-28 hz, though? 27-28 is plenty low for a car sub. You can do 22-25hz, it's just going to take a LOT of port length to get it (28 hz will take a lot, too). Either or, really, I wouldn't go much lower than 25hz in a car setup personally, simply because you won't find that much music that will drop lower than 30hz. Plus a car has cabin gain.
 

Silver Member
Username: Suleman36

Post Number: 790
Registered: Feb-05
I did however there was a guy on the soundillusions forum for ascedantaudio that tried a Avalanche 15 in a 3.5 cu ft ported box tuned to 28 and he said it was way to boomy because the actual resonant freq is 15.7 which is lower then most subs. Here is what he had to say in that forum

"why don't you plot it in some box building programs and see the nasty peak from 40hz-50hz and an f3 of like 38hz in a 3.5 cube box tuned to 28hz like mine. I had to drop about 18db at 40hz in my car to get it to sound natural. Low low end was non existent without EQ because 45hz was so loud that i couldn't even hear or feel 30-35hz. With sealed my low end below 40hz is MUCH MUCH better that just goes to show that tune is too high All subs are different, some subs, like say an E12a can go in a small box tuned to say 28hz and still have GOBS of low end. Some subs like the Temptest and Avalanche need to be tuned low if you want anything resembling music in your car.

I own the sub so i should know, i really need to discuss the recommended ported enclosure specs with chad because i think he needs to recommend a lower tune at least 24-25hz. And a tad larger box around 4 cubes.

All the box builder programs i've plotted say 4-4.5 cubes tuned to 18-22hz for the avalanche. All of them recommend sealed over ported for it too.

One thing i will say is the this is one of the loudest subs i've had in a sealed box, VERY efficient and VERY loud for being sealed using way less than 1000w. It has so much low end sealed you'd think it was ported already! It models up extremely close to the brahma, and even more low end than the X X X in the recommended boxes. brahma 15" actually needs an even bigger box for .7 QTC but i like low QTC ~.6 for best possible transient response".
 

Silver Member
Username: Suleman36

Post Number: 791
Registered: Feb-05
we're not talking about box size we are talking about tuning frequency. I think the fs of the avalanche is 15hz if i'm not mistaken which is the main reason low tuning is necessary. I wouldn't just say this if i hadn't heard it for myself. At first i was like eh
wtf? And then i plotted it on my programs and sure enough, exactly what i heard a HUUUUUUUUUUUUUUGE lump at 45hz i'm talking like HUGE peak and then an f3 of 38hz or something which is ridiculously high considering its ported. My sealed box has an f3 (without cabin gain) of like 32hz.

I've never even considered tuning any sub i've had below 26hz before, normally i tune around 28-30hz. Its only with this sub that i've found it neccessary. i just don't want to see a bunch of people buying avalanches throwing them in these boxes and then being dissappointed with their SQ. I'm trying to help here, not argue.
 

Gold Member
Username: James1115

Wilton, Ct

Post Number: 2444
Registered: Dec-04
is there a broken record on this forum Jon? I swear I hear the same question every single day. lol
 

Silver Member
Username: Suleman36

Post Number: 794
Registered: Feb-05
if you can fit that much room i would go with 4 cubes tuned to 22hz. Believe me it will be LOUD even with that low of a tune, but its too peaky in the 40hz region with anything above 25hz tune. Just means a little bit longer port. The box i'm recommending is the perfect box for the avalanche. If you want great SQ and don't have a 1/3 octave EQ, and want great bass
in the 25-35hz region don't tune above 25hz. Even at 22hz theoretically you'll be 4db up at 30hz than sealed, and 3db up at 40hz, and 2db up at 50-60hz than sealed.

With the recommended 3.5 tuned to 28hz you have a ridiculously nasty peak at 40hz. I had to lower my EQ BIG TIME at 40hz to get it to sound good.
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 3746
Registered: May-04
"I've never even considered tuning any sub i've had below 26hz before, normally i tune around 28-30hz. Its only with this sub that i've found it neccessary. i just don't want to see a bunch of people buying avalanches throwing them in these boxes and then being dissappointed with their SQ. I'm trying to help here, not argue"
Results do differ, glad you looked around and got opinions on it, though. Research is important. Anyway, I was basing my tuning recommendation on results I've seen from Brahmas and X.X.X's, and other 15" subs that I've dealt with, but it seems the Avalanche was designed to be sealed and I haven't had a chance to plug it into WinISD and see.



"we're not talking about box size we are talking about tuning frequency. I think the fs of the avalanche is 15hz if i'm not mistaken which is the main reason low tuning is necessary. I wouldn't just say this if i hadn't heard it for myself."

Box size is just as important as tuning frequency, and affects the frequency response of the system by a huge amount. If the box size isn't optimal, you will get a lump in the frequency of the box, especially if the box is too small or way too large. From what it sounds from his results (f3 of 38hz), it sounds like the box was too small. And it sounds like it's an issue of the box and not the tuned frequency. Try running ISD or similar and making the box a little larger. The resonant frequency doesn't necessitate the tuning frequency, BTW.
 

Gold Member
Username: James1115

Wilton, Ct

Post Number: 2445
Registered: Dec-04
MO just go sealed I told you already it is very very loud as in you wont ever need any louder in a DD.
 

Silver Member
Username: Suleman36

Post Number: 796
Registered: Feb-05
and actually you can use the 3.5 cubes that is good size, its just the tune that needs to go down. I think you should seriously only go as high as 24hz if you like SQ at all and listen to alot of complex bass music. I listen to alot of VERY demanding metal/rock/alternative music and without the tune i'm recommending it just doesn't sound like i wanted without EQ. THe sub itself performs WONDERFUL its my favorite sub EVER. But using the wrong enclosure on any sub can ruin the sound of a sub. But i was able to correct the sound to make it sound great with my AC EQT.
 

Silver Member
Username: Suleman36

Post Number: 797
Registered: Feb-05
Im starting to wonder about this sub in a ported box because of all the mixed suggestions... I guess sealed is the simplest way to go just like james has had his since day one and will probably blend in with my front stage better to with the sq and save me more space.
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 3747
Registered: May-04
Alright, just ran it. That subs an oddball in it's design. I screwed up when I read the Vas on that sub, the Vas on that thing is HUGE compared to other subs that are similar like the Brahma and X.X.X. His recommendation would work well with that sub.
 

Silver Member
Username: Suleman36

Post Number: 798
Registered: Feb-05
So he was right all along huh jonathan????? lol

So are we talking 22Hz-25hz ? what do you think man?? good thing i brought it up in this thread
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 3748
Registered: May-04
Yup. I'm willing to admit I'm wrong about something :-) Like I said before, I haven't dealt with the Avalanche, I was basing upon Brahma/X.X.X. experiences since they're a similar design. Looking at the specs, it seems that it was designed to be efficient due to a very loose suspension, which is what screws up results ported. When I ran it, 4.25 net tuned to 20hz gave the flattest response. That's going to take a lot of port, though. Sealed would be loud, and would likely give best results with that sub. The more I look at that sub, it isn't really designed to work optimally ported, at least not for SQ purposes.
 

Silver Member
Username: Suleman36

Post Number: 799
Registered: Feb-05
That is well said. Its interesting because i talked to chad which is the owner and designer of AA and he suggested 26hz-30hz. That guy that gave me his port measurements says he needs to have a talk with chad regarding the 26hz-30Hz tuning. After investigating this topic for over a week i finally made up my mind to go sealed at 2.5 cubic feet like james has his and call it a day. Thanks for your input aswell jonathan. I will let you know how it goes.
 

Gold Member
Username: James1115

Wilton, Ct

Post Number: 2447
Registered: Dec-04
good choice MO do you want the dimensions I used.
 

Silver Member
Username: Suleman36

Post Number: 801
Registered: Feb-05
Yeah that whould help james..thanks
 

Gold Member
Username: James1115

Wilton, Ct

Post Number: 2449
Registered: Dec-04
16(H)x16(d)x 24(W) the front baffle is doubled up to 1.5in so take that into play! those are outer dimensions.
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 3750
Registered: May-04
The bad thing for Chad would be that you can't really recommend that much box to most users. 3.5 net is a big box in itself, but 20-22hz is a LOW tuning frequency, something you'd see in a home and not a car, reason being is that it requires a lot of box and a huge port, especially in the case that you want a large enough port area to prevent port noise.
 

Silver Member
Username: Suleman36

Post Number: 802
Registered: Feb-05
Are you using polyfill??? and also what differance does it make if i go bigger then 2.5 like to 3.5 for example??
 

Bronze Member
Username: Mixneffect

Orangevale, Ca. USA

Post Number: 55
Registered: Apr-05
The program i use is called BassBox6 Pro. This program is ok. It is not the best program, but it is great for box building. It beats the slide rule ... lol

You can find it at www.madisound.com for about $180
 

Silver Member
Username: Suleman36

Post Number: 807
Registered: Feb-05
Jonathan, for those who wanna go ported on the Avalanche that have smaller amplifiers like 500 watts rms for example. How big should the box be and what should they tune it to?

I came up with 3.5-4.0 tuned to 20-25hz tops.

Now for those who have a bigger amp like 600-800 watts rms it whould be recommanded to stay sealed at 2.5-3.0 cubic feet. Let me know if that sounds legit.
 

Bronze Member
Username: Creative

Newark, CA USA

Post Number: 13
Registered: Apr-05
That's a pretty good price for that program.
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