Porting my type E's need some help guys

[Bumpin Expo]

Well i want to port my type E's but i need some help. The alpine website only gives specs for a sealed box which is .8 to 1.7. What should I put for the airspace on a ported aplication? Thanks guys

[TBSpyder]

Ported boxes are usually bigger. But if Alpine doesn't have a recommendation that might mean they aren't meant for a ported application. If you want to try it anyways...I do something like atleast 1.7 cubic feet.

[Bumpin Expo]

Yeah it says recc. for bandpass and sealed. If i port it will it mess up or sound bad?

[aaron1017]

My best bet would be to donwload WinISD Pro from HERE (http://www.linearteam.dk/) and input the speakers specs. This will allow you to see the performance of the box, the box size, and the port length and diameter.

[TBSpyder]

Originally posted by Afboy143
Yeah it says recc. for bandpass and sealed. If i port it will it mess up or sound bad?

If anything...just sound bad.

My best recommendation would be to find out first hand from someone who has already done it. Get onto a car audio forum like www.caraudio.com or www.sounddomain.com and make a thread asking if anyone has your subs ported and how they sound.

[Bumpin Expo]

I jus dont wanna go thru all that mess jus to find out the damn subs sound bad. I hate building boxes as it is. But i posted on caraudio.com and someone has yet to reply for 4 days nw :-/

[93ex]

just win isd it

[Bumpin Expo]

i have no idea how to work that thing

[MDIFYTD]

Don't worry about it man, T/S stuff can be a little confusing. I'll do it for you tonight when I get off work :thumbup:

[Bumpin Expo]

damn man thanks, that means a lot. I just really want to get this box done that way when i get it all for xmas i can put it in

[MDIFYTD]

no problem

[MDIFYTD]

So are you dead set on doing the Type E? The reason I ask is because Type E and ports don't seem to like each other... pretty far from a flat response.

But if you're gonna do it 2 cu ft tuned to 20hz gave a very similar curve to the sealed box but with a nice gain. FYI you'll have a definate hump in your frequency responce from about 40-80hz which will make some music sound unbalanced but hey if you listen to rap that's where most of the bass happens anyway. It just depends on what your after...

BTW that's 2 cu ft after speaker and port displacement. And a 4" diameter port must be 39.23" long to be tuned to 20hz in a 2 cu ft box. So you're port will displace .277 cu ft and your sub will displace .086 so make your internal dimensions for a gross volume of 2.4 cu ft

[rangcrx]

why would you ever want to port a sealed box?you may have tp much flo ande your subs underlow bass will sound like shit and popping,i mean and in a big airspace like a Suv a sealed is better and give you that hit in the chestBass everyone wants

[Bumpin Expo]

so i should just stick with the sealed type E 's? I just really wanted to go ported because i was gonna spend all this money on a amp and i wanted to get the most sound out of my shit. I guess ill jus build one huge sealed box for 4 12's and go with that

[93ex]

if you want to build a ported box, build a ported box, dont just cut a hole in a selaed box.. tun on the subsonic filter and lets have fun

ported is awesome in a big suv, since you have the ROOM to make a 3 or 4 cube box without a problem

[aaron1017]

If you are gonna continue to be into car audio... it would be wise to get to learn WinISD, also read about T/S parameters. Jesse gave me this link...

http://www.welcometotheden.8k.com/caraudio/TheileSmallparameters.pdf



To elaborate on what was said earlier in teh thread by MDIFYTD...
Since the Type-E don't give a flat responce and don't seem to be ported well, you will probably have to tune to a low frequency. The lower frequency you tune the ported box to, the longer the port length have to be since lower frequences have a LONGER wavelength. Making room for that long port requires a much bigger box.

You also have to take into account "port noise" from the air pumping in and out. Speakers with more volume displacement (Cone area x Xmax) require wider ports... and the wider the port the LONGER it must be. So you want the minimium port diamter so decrease the port length. Here is a quote taken from one of Adire Audio's webpage HERE. (http://www.adireaudio.com/tech_papers/vent_sizing.htm)

For a Helmholtz resonator to work requires two reactive acoustical elements: an acoustical compliance, supplied by the volume of air in the box; and an acoustical mass, supplied by the port. As you may know, the acoustical mass in the port is directly proportional to the length of the port and inversely proportional to the square of the port's diameter. This is why when you increase the diameter of the port, you must increase its length to maintain the same acoustical mass.

But to behave as an acoustical mass, the air in the port must essentially he moving as one. Implicit in this is the requirement, then, that all port dimensions must be substantially smaller than a wavelength of sound. As one of the dimensions starts to approach a wavelength, the port no longer acts as an acoustical mass, but begins to exhibit the behavior of an organ pipe or even a transmission line. Not all the air is moving in the same direction, and the port no longer behaves as a single mass.

So, clearly, we have a set of limits imposed by the requirements that the port act as a single lumped acoustical element. The diameter must be small enough so that it is a tiny fraction of a wavelength in the region of the Helmholtz resonance. At the same time, port length resulting from the diameter must also be a tiny fraction of the wavelength at these same frequencies. Using an arbitrary notion of "tiny" as less than 1/10 of a wavelength, this would suggest that the largest dimension of a port operating at 50Hz (wavelength is 20') would be a 2'.

I would, personally, adopt an even more conservative figure, such as 1/15 or 1/20 the wavelength, suggesting that a port tuned to 50Hz should not exceed about 16" in length. This is because the port is not just acting at 50Hz, but over a substantial range of frequencies above and below this. Imagine, also, that a 2' long port will exhibit its first standing-wave resonance at the low frequency of only 250Hz, where the output of the port increases substantially.


What a Helmholtz resonator is... (http://www.sfu.ca/sonic-studio/handbook/Helmholtz_Resonator.html)

[Bumpin Expo]

First of all IM BUILDING A WHOLE NEW BOX. Im not using existing sealed boxes. I want to put 4 12" Subs in my car but im going to make 2 different boxes. I was thinking of making each box 4 cu/ft before all the displacement. Tune it to 20 Hz using a 2" Diameter port. In order to get 20hz it would need to b 5.29 inches long. Now how much louder would this box get over a sealed box, all i listen to is rap. BTW thank you So much everyone for all the help. I have had SOOO much trouble with all this ported box stuff thats why i always made sealed but thank you everyone for the help. I also didnt know if u used a smaller diameter port that it would require a less amount of tube to get the hertz as comparded to a larger sized port.

[Bumpin Expo]

Also another option for me might be getting two of the brand new 12" Polk MoMo subs and port them ( http://www.polkaudio.com/car/specs.php?name=mm2124 ) . I would make each chamber 1.5 b4 displacment and port to 30 Hz? And run them off the 600 watt xtant amp or should i get the 1000 Watt MTX like i was going to? I mean if the alpine type E's wont sound good id rather get these Mo Mo's and port 2 if they would slam even more. Again i wanna thank you guys so much for puttin up with my newbieness

[Bumpin Expo]

"You also have to take into account "port noise" from the air pumping in and out. Speakers with more volume displacement (Cone area x Xmax) require wider ports... and the wider the port the LONGER it must be. So you want the minimium port diamter so decrease the port length."

So if the Xmax is a larger number i need to make the ports wider? Cant i jus use 2" ports the whole time or i have to make it larger

[93ex]

Im at school, so I cant runthe specs thru WINISD, but why not like type R's or somethign ofthe like..i know youre stickign with CC stuff..

[Bumpin Expo]

the mo mo site gave directions on how to make a ported box but it says it would b tuned to 40 HZ then Fe3 would b 36.5 hz. This is using a 4in diameter port 10 inches long. Could i use this plan and tune it down a bit? God i feel like im askin too much lol

[Bumpin Expo]

well yeah i work at CC and i get discounts there so thats why im doin their stuff. I dont have to kno this kinda shit at CC. I jus need to kno sealed boxes and what amps go good wit wat subs not al this other stuff

[Bumpin Expo]

And i was going to do type R's but they are back back back back ordered. I was thinking of going with the new polk momos?

[aaron1017]

This might work for port diameter. http://www.mhsoft.nl/PortLength.asp

but if not, you can aleady calc it by hand :cool:

[MDIFYTD]

Tune it to 20 Hz using a 2" Diameter port. In order to get 20hz it would need to b 5.29 inches long

To keep port mach to an acceptable amount for a common chamber box for those 2 12's you would need a minimum of 25.64 sq in of port area or a 5.7" round diameter. Anything less and you'll get some nasty port noise

So if the Xmax is a larger number i need to make the ports wider? Cant i jus use 2" ports the whole time or i have to make it larger

you could use 2" ports but you'd have to use multiple ports.

the mo mo site gave directions on how to make a ported box but it says it would b tuned to 40 HZ then Fe3 would b 36.5 hz. This is using a 4in diameter port 10 inches long. Could i use this plan and tune it down a bit

by making the port longer you could change the tuning frequency but don't just guess at the length make sure you run it through a calc.

[Bumpin Expo]

Ok I made plans, tell me if this is good

Im going to make a 3 Cu/Ft box for 2 12" Polk Mo Mo Subs. I did some research and found out that 30 Hz would b about the best for rap music. I came up with 3 cu/ft cuz each sub needs 1.5 in a ported app. Im going to make both subs firing up with the port in the middle. Its going to be 12.5 Inches long and the diamater of the port is going to be 4" . Can someone tell me if this plan sounds all good?

[MDIFYTD]

Way to small a 4" round port is 12.5 sq in of port area. Those two subs tuned to 30hz require 62.5 sq in of port area :o probably have to go with a slot port something like 15x4.25 with a length of 55" :o

check out this port calculator:

http://www.carstereo.com/help2/Articles.cfm?id=31

[Bumpin Expo]

my god this shit is confusing as hell! Ok i got how u got 62.5. Now how do i calculate a port using that calc u sent me? Also how would i figure out how much space that port is going to displace from inside the box? Is it really worth all this trouble to go from sealed to ported?

[MDIFYTD]

A round port is just a cylinder, right. So to solve for a 4x10 round port we'd just use the formula for volume of a cylinder...

(pi)(radius squared)(height or in our case length)

(3.14)(4)(10)=125.6 cu in or .07 cu ft

A slot port is just (L)(W)(H)

[MDIFYTD]

Now how do i calculate a port using that calc u sent me?

Just scroll down the page the length calculator is down there.

Is it really worth all this trouble to go from sealed to ported?

Well like I said it depends on what you're after... you'll definately gain some output by going with a ported box.

Honestly, if I were you I'd look into some other subs. Adire audio shiva or tempest would be killer subs and they're cheap too. Two Tempest each in 4 cu ft ported @ 24hz with a 1200.1 on them Watch out! More than enough to satisfy your basshead :D :D

[Miles]

Originally posted by rangcrx
why would you ever want to port a sealed box?you may have tp much flo ande your subs underlow bass will sound like shit and popping,i mean and in a big airspace like a Suv a sealed is better and give you that hit in the chestBass everyone wants

can we try this again in english please?

[MDIFYTD]

Originally posted by saggleman
can we try this again in english please?

:lol:

[Bumpin Expo]

yeah i c what u mean. I jus wanted to use the Circuit city subs only cuz i get a big discount and i can return em for the next 5 years if they blow. Or i can trade em in and get somethin else within that time period. Well im jus gonna try n figure somethin out myself with this damn ported thing. I jus wanna build a 3 cu/ft box tuned to 30 hz. Ill get back to u when i find somethin out thanks for all the help man

[93ex]

nothign against you.. most people in the industry doit too.

I can get cost on jl and mbq and alpine.. but i only have jl amps.. i like thier ohm load fun... but i went with a ed12a since the closest thing in the jl lineup is the w7 which i didnt want ot use...

[Bumpin Expo]

nice nice, how u got the hook up on alpine? Im not too much of a fan of JL. I see it everywhere and I get sick when everyone tells me how much Jl and Audiobahn are the shit. Thats all i ever hear at work, "Damn you got those audiobahns, they are the shit. I had a setup bla bla bla but it blew..." lol and people always ask why we dont sell JL or kicker. O well we mostly sell out MTX and alpine neways. But yeah i wanted to go wit Elemental or the magnum d2's but thats gonna b farther ahead once i learn a lot more on enclosures and the such

[93ex]

friends

and why dont you like JL?

[Bumpin Expo]

yes i kno they are like one of the best out there and the w7 is one of the most advanced subs out there bla bla i get flamed for it all the time. Im jus not a big fan of JL. its like a civic, everyone has one, and they reason they do is cuz they are good and realiable. But in JL's case they are overpriced and they kno they can do it and people will pay it. Like what rockford did with their products. Back in the day they made kick ass products and now they make shitty stuff and charge the same or more as they used to but since they got that rep. they kno people will pay. JL is over played and for the price u can get shit much cheaper IMO. i kno im gonna get flamed at least once but some hardcore JL lover like always but o well YOU CAN BLOW ME. Just like damn audiobahn lovers. Audiobahn plain sucks except for the amps which are still over priced. I have no idea how audiobahn got the name they did? Havent they always sucked?

[93ex]

so you dont liek because its popular..yet you own alpine...

I like JL amps. Subs are nice, w7 is good, but imho brahma or XXX is better than the w7, DD is also right up there.. but peopel are paying and that is capitalism.. i dont really like the jl comps or coax anymore, ive heard stuff I prefer over them.. but its all a matter of opion.. as to what you think SOUNDS better.

and yes you cna get much cheaper shit..but you get what you pay for.

Audiobahn is where they are because peopel like the shiny stuff...and have no idea about sonic accuracy..they want loud, and 98 percent listen to rap 24/7.. and in many reviwes audiobahn had a sweet spot @ ~45hz, a nice little bump...

[aaron1017]

I think the W7 is one of the top best subwoofers made today.... but not the BEST for the MONEY.

[Bumpin Expo]

tru tru i wanna get some bad ass subs like the XXX when i get all this ported shit down, i guess tomarrow at skool i got a lot of learning during computer class! Once i get it somewhat down im goin to CC and trading in my Type E's for Momo's and tryin to buid my self a ported box. Thanks to all for the help, mad props to MDIFTYD and aaron for all the info. WtF does that mean neways? mdiftyd??

[MDIFYTD]

No problem man, I'm glad to help.

It's a crack ass way to spell modified. Thought about changing my name to what it is on every other forum I'm on, which is SSgfunk, but I have quality points now, lol.

[mel_ms]

screw the type E's and do two type R 12's. They are cleaner and you would get almost the same performance and you will not have to drive around with all the weight. I use to sell and install them. The type E's are good subs but the type R's are better. If you already have the subs.... dont port them... They sound better in a sealed box and you will have better bass response.

[aaron1017]

At least the Polk MOMO looks better WinISD's than the Type-E's did.

[Bumpin Expo]

yeah thats what i figured aaron because the momo website accually gave some specs to a ported box on their site. So mel u think i should jus keep the box i got now and throw 2 type R's and a bigger amp in? The type r's are on back back order and i didnt really wanna go wit a bigger amp but i mean i guess if its gonna b better than 2 ported momos on 600 watts i might do it

[mel_ms]

i used to work at circut city and thats why i know about them so much. I definitely would do the R's over the E's. Four type E's is over kill and the two type R's are perfect. I did four type R's in a suburban off of the 8100d and that shit was sick. The roof of the truck was like a piece of paper. Which store you worked at?? I worked at clear water,port richey,Dale mabry and the last one was citrus park over a five year period.I might come back part time.... not sure yet tho nick and preston are trying to see what they can do..

[mel_ms]

oh ya those mo mo's are clean but they blow real easy if you dont break them in. it took the one on display a month before it sounded right. In the suburban we did three of them and he would blow them one a week. I told them to do four type r's because of the ohm load but no one listen until like 15 subs later. you can ask either aaron, joey or preston at citrus park loc 3269

[Bumpin Expo]

Hey mel, i work at citrus park. Pshh Joey dont kno nething i dont listen to him nemore LoL. And yeah I had the mo mo's, I did that mistake of not blowin them in and thats why i went from those to type E's. yesterday i got preston to try n order me some Type R's and they are NATIONAL BACK ORDER! Alpine cant make nemore so now im fuxed. Also we sold out of 1501 D's. And yeah I heard about that suburban, Joey told me about it. And all his shit got jacked :mad: kinda shit like that pisses me off. What was ur name over at Citrus Park? I was a daily customer there thats why mark got me a job but its only seasonal. U got AIM?

[mel_ms]

AFBOY its Melvin and i talked to P amd i might work there part time again.