T-Line Box build

 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 171
Registered: Mar-09
Me and my buddy researched t-line box builds after we went to a local car audio shop and had the owner explain tried to explain them to us.

It is actually considered a quarter wavelength box and the port is roughly 7 feet long.

The port area had to equal the cone surface

We put a power acoustik mofo in the tline box and it was louder than 3 mofo's in a ported box 7 cubes tuned to 34 hertz.

I know we need better equipment, but hey we're poor kids lol.

Its 3/4 mdf, 45'd all the corners in the port.



Upload
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 172
Registered: Mar-09
Upload


I'm having a hell of a time uploading photos so when i get back from class i'll put some more up.
 

Silver Member
Username: Boomtank

Rochester, NY USA

Post Number: 676
Registered: Oct-06
I've built t-lines in the past. They work real well with isobaric loading. Had one for 2 treo tsi 12" 40hz in an s10 ext cab. Was very loud on 800wrms.
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 173
Registered: Mar-09
do you have any pictures or links? i think i have the wrong idea on isobaric loading. isn't it where both are just facing each other or pretty much right on top of one another?
 

Silver Member
Username: Boomtank

Rochester, NY USA

Post Number: 677
Registered: Oct-06
yeah they can be in phase or out of phase. "Stacked" or "reversed".

Upload

you can then double to power and keep the same cone area hence the same size enclosure.
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 175
Registered: Mar-09
that wouldn't affect the size of the port? because with the way we went the port equaled the surface cone area
 

Silver Member
Username: Boomtank

Rochester, NY USA

Post Number: 678
Registered: Oct-06
Isobaric loading is like having one cone. Both cones move together creating a woofer that can handle twice the power with the same cone area.
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 177
Registered: Mar-09
thanks for the info. Do you think it would be louder/ sound better if we went the isobaric route, or build an identical box.

again really appreciate it.
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 178
Registered: Mar-09
anyone know?
 

Platinum Member
Username: Insearchofbass

York, Pennsylvania

Post Number: 12846
Registered: Jun-04
isobaric loading uses two drivers but gives the output of one. But you gain twice the power handling so you would gain +3 db by going with that design if you have twice the power you did with the single sub.....the sound is supposed to improve in the lowest frequencies using isobaric design
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 179
Registered: Mar-09
thanks sean and eddy

So my final question is

Which would have more output

2 seperate, but identical Tline boxes

Or One tline box with isobaric loading?
 

Silver Member
Username: Boomtank

Rochester, NY USA

Post Number: 679
Registered: Oct-06
2 identical enclosures would yield a higher output since you have twice the cone area and the same amount of power. Yet you have twice the space occupied.

If space is an issue isobaric loading is the answer. If you have room for 2 identical enclosures go with that.
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 180
Registered: Mar-09
space isn't an issue. its a blow through on an old 78 f150 long bed.

thanks for the help
 

Gold Member
Username: Ducka

Shelby Twp., MI United States

Post Number: 1285
Registered: Jan-08
What are the pros and cons of a t-line? Might build one for the IDMAX...
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 181
Registered: Mar-09
It's a box built specifically to the specs of your sub. It has great low end and gets plenty loud as well.
I'd say the cons are just the size of the box and the build is more complicated. Other than that i think its the way to go.
 

Silver Member
Username: Simple_smith

Lapeer, Michigan United States

Post Number: 148
Registered: Dec-08
ugh now i want to try a t-line box...

do you figure it the same as a ported box, but with the port area being = to the cone area?
or is it totally different?
 

Gold Member
Username: Ducka

Shelby Twp., MI United States

Post Number: 1289
Registered: Jan-08
I feel like this is a really stupid question, but how is port area calculated?
 

Silver Member
Username: Simple_smith

Lapeer, Michigan United States

Post Number: 149
Registered: Dec-08
heigth x width of port

so if a port is 5" wide and 10" tall, you have 50 Square inches of port.

to calculate the necessary port area, it should be 12-16 square inches of port area per cubic foot of internal volume.
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 182
Registered: Mar-09
the procedure we used for ours was the port area = speaker cone area

the way we found our dimensions was

1130(speed of sound) divided by your tuning, we tuned ours to like 34hz. which gives us 33 roughly. 33 feet would be the full sound wave, and since ours is a quarter wave box it needs to be divided by 4

33/4 = 8.25
8.25= port length in feet.

does that make sense?
 

Platinum Member
Username: Rovin

1 15 = 152.5 DBs ...Trinidad & T...

Post Number: 15622
Registered: Jul-05
is that all there is to it ?

built alot of boxes but never tried Tline since its usally pretty big & takes up alot of space

is this formula the same weather its a 6" - 18" sub...?
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 183
Registered: Mar-09
yeah the only thing that changes is port size due to the cone area of the subs.

at least thats what i've gathered anyway.
 

Platinum Member
Username: Rovin

1 15 = 152.5 DBs ...Trinidad & T...

Post Number: 15623
Registered: Jul-05
say for a 10" sub

do u check the cone area as the outer diameter of the speaker frame since some 10s wud actually be about 11" while others will be about 10.25" or do u just check it as 10" ? ....
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 184
Registered: Mar-09
you don't measure the surround, just the cone. for my ten's cone was like 9 inches in diameter.

i had something like like 63 inches of surface area.
 

Gold Member
Username: Ducka

Shelby Twp., MI United States

Post Number: 1290
Registered: Jan-08
Would anyone mind helping me figure out proper port area+ length for my IDMAX. I think it could be amazing in a t-line. If you wanna be really nice a drawing would be sweet.

Cone area of the IDMAX is 545cm^2 which i think is about 84.48in^2

That seems like a pretty large port to me... Is that right?

If I'm doing it correctly I would need like 15Hx5.6W and say I wanted to tune to 34hz like you did I would need 8.25 ft of port depth?

As far as the corners of the port, Do I need to take into account putting in 45degree angles and make the port longer?

Anyone have more info on building T-lines?
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 185
Registered: Mar-09
I forgot to mention the Fs of the sub is what you want to use your tuning.

Because then the enclosure of the tline would be best for your sub.

http://www.stevemeadedesigns.com/board/index.php?showtopic=1828

that guy does a lot better job at explaining it than me
 

Gold Member
Username: Ducka

Shelby Twp., MI United States

Post Number: 1291
Registered: Jan-08
That was a very helpful link. I'm definitely going to have to look into building one for my IDMAX if I can keep th ebox small enough to fit in my trunk.
 

Platinum Member
Username: Rovin

1 15 = 152.5 DBs ...Trinidad & T...

Post Number: 15624
Registered: Jul-05
nice - i will take a better read of that link later when i have time to absorb it all

i have a RE SE 10" i want to practice a T line with just for the experience ...
 

Gold Member
Username: Hittin1

TEAM REVOLUTION, La. Lake Charles...

Post Number: 4114
Registered: May-07
i would like to see Rovins completed box.. He always does nice azz builds..
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 186
Registered: Mar-09
out of all the tutorials i've read about t-lines that guys was the best imo.
 

Platinum Member
Username: Rovin

1 15 = 152.5 DBs ...Trinidad & T...

Post Number: 15631
Registered: Jul-05
i know a guy who did 2 10s RE SE tuned 34hz , powered off a PPI 1500 & he did 145 @ about 44\45hz peak with it but of course the box is BIG , its about 24" x 44"

with my 2 10 RE SE in a sealed S box it did 140 so i'll be glad to try 1 10 in T line to see what it does , maybe later on this wk when i get time since i have a 2 12s pro audio mids\highs box to build for a guy & im going to start work on it today ...
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 187
Registered: Mar-09
definetly let us know how it turns out
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 191
Registered: Mar-09
has anyone ever played around with a folded horn enclosure? it seems similar to this.
 

Gold Member
Username: Dustin3

D&L Audio Tech.Dustin

Post Number: 5166
Registered: Oct-05
Rovin,

Thats great your doing a pro audio build. Let me know if you need any help designing it or ideas with it. We do pro audio builds for clubs, frats churches etc locally here.
 

Silver Member
Username: M0nstar

Toledo, OH U.S.

Post Number: 385
Registered: Dec-08
ont he install that you have pics of, when you 45'd the corners of the port, did it matter where you put the 45 angle at? how big it was? dont you have to maintain that same port area all the way through the port, and if so, wouldnt it be BY DEFFINITION impossible to do if the ports werent kinda rounded instead of 45'dd..

thats gonna be really hard to understand if we're not on the same page.
 

Silver Member
Username: Boomtank

Rochester, NY USA

Post Number: 684
Registered: Oct-06
you must maintain, as much as possible, the same port area throughout the port. 45's are the best way to get it closer. Without the 45, it is way off in the corners. The only way to keep it is to not bend the port, use aero's, or curve the mdf around the corner.
 

Silver Member
Username: Boomtank

Rochester, NY USA

Post Number: 685
Registered: Oct-06
Also, you want to place the 45 as close to the port width away from the corner. so it stays as close as possible to the same port width throughout the port.

PS. you forgot one of the 45's at the last turn of the port, bottom right of the picture.
 

Platinum Member
Username: Rovin

1 15 = 152.5 DBs ...Trinidad & T...

Post Number: 15634
Registered: Jul-05
Bassman3

thanks 4 the offer - will look u up when i need it

what im building right now is this 4 a guy

http://www.speakerplans.com/index.php?id=mt122

furnished it but i dont have any pics right now since my bro has my cam & he lives about a hr away ...im hoping he brings it back b4 i hand this box over to the guy

it SUX @ss to be working with mm ...
 

Bronze Member
Username: Pacci1er

Post Number: 21
Registered: Nov-09
Some help if you could. I'm trying to design one of these tlines for my sub. But the main area where the sub is, that is never talked about. Is it just some of the port area with added displacement? or is it some other dimension that I'm just over looking? Thanks.
 

Bronze Member
Username: Pacci1er

Post Number: 22
Registered: Nov-09
IDK if your wrong in your design but I have found this diagram and it is different from your design.

Upload}

This is a tappered version for lower fresquency subs but it is still the same concept. An well your design seems like the placement of your sub will reflect the sound wave back to the speaker.

Is there anyone with more knowledge of this box design. That link you have all the pictures are corrupt so that is no help. Please help. I'm am trying to desgin one of these boxes.
 

Silver Member
Username: Domenico

Glendale, AZ USA

Post Number: 170
Registered: Apr-09
does the size of your bed come into play when making a blow through?
 

Silver Member
Username: Dangeranger

Fredericktown, Ohio United States

Post Number: 201
Registered: Mar-09
just effects the size of your box.
 

New member
Username: Creator1

Canada

Post Number: 9
Registered: Nov-09
Isobaric is so u can 1/2 the vas! Allows u to put say a 15" speaker in a box 1/2 the size. But- its less efficient. Just allows u to use a larger speaker in a smaller box. BUT- then ur throwing away money on the 2nd driver- cuz the cone area isnt utilized?
SO why not just spend ur money on the proper drivers for the size of box u can build for the space u want to use up? If u go ported say, then each time u Double the cone area, u gain 3 db (unless each speaker receives the same power )ie: 2x 10's, then 4x 10's , then 8x 10's then 16x 10's. THE more drivers and cone area- the MORE output given the same power. IF u dump 3000 watts to an 8" sub- it can only mover so far and only move so much air. Better to go MORE cone squares :-)
 

New member
Username: Tgspeedracer

Highlands ranch, Co Usa

Post Number: 4
Registered: Nov-09
^^^ so 2 10's > 1 12"
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