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SpeakerBoy

Building a Transmission line

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Duran, i think he wanted to know how big it looks in real life. ;)

(Big pictures)

P1020448.jpg

Friend of me holding the top piece.

P1020421.jpg

Dog guarding the wood. :P (dog=golden retriever, so a quite big dog.)

P1020423.jpg

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Duran, i think he wanted to know how big it looks in real life. ;)

(Big pictures)

P1020448.jpg

Friend of me holding the top piece.

P1020421.jpg

Dog guarding the wood. :P (dog=golden retriever, so a quite big dog.)

P1020423.jpg

:faintthud:

Did you build that just for me? :D

Thats monstrous, for a 10" woofer......

Does she sound good?

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WOW!! That box looks too much like work. Too big and too heavy for my truck. Nice carpentry skills though. I'm glad we kept mine simple. I just used alot of 4" pvc. Best of luck to ya sir.

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Yes, it sounds very good, only minus is that i have a peak at 43hz, but that can have a lot to do with room acoustics.

Before the Tline i didn't listened a lot to rock, but now i like to hear and feel the kickdrum.

@Cablguy, thx.

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Man them t-lines are a mission but it don't look like many cars could fit that type of enclosures.

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Man them t-lines are a mission but it don't look like many cars could fit that type of enclosures.

Hence why you really don't see them in vehicles. They just aren't practical.

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Just PM Shizzon. He knows EVERYTHING about EVERYTHING without knowing ANYTHING.

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I have saved a little money for some wood, and still have glue, clamps and screws from my other box. I wanted to give building a T-line a try since i have heard fairly good things about them. It's just a for fun box, for my 12" visonik i got a while back. Amp and power and all that is covered, it's going in the house for now (no car til who knows when >.<). it's for music, primarily low notes in rap music. i was gonna try for a tuning of ~27-29hz. Now on to the hard part.

I havent had alot of computer time recently, but in the time i have had, i couldnt find a calculator for a 1/4th wave transmission line. The specs i can give you for my sub: 250rms rated (takes double fine for a couple hours) 8mm xmax between 6"-8" mounting depth, and overall, in every box i've had it performs extremely well for a $20 sub, brand new.

How do i calculate length for the line? Box will be 3/4" mdf. Size Is Not an issue.

Thanks for your answers, looking forward to this project.

Gotta get this done, severe boredom and grounding has landed my poor sub in a cardboard box (took the time to reinforce and deaden the cardboard too ). Sadly it still sounds better than my radio :trippy:

here is line length tLL = 0.25 x c' / fs. were c' is equal; to the speed of sound 13560 so 3390 divied by your fs of the sub. to get t-line length in inches

also these guys are right you do not need a box this big most people use the easy way of doing it so it will fit they will tune it between 48-35 hertz which is 6 to 8 foot how to find were your tuned at is take the strait line down the center of the line and devide by 3390 to get the hertz were the box is going to peak at.it will drop off after this point. a 7 foot long line will play down in the 20 hz range no problem. does not mean it will be loud at 20 hertz

area of the line opening is based on sd of the sub if you go larger you will lose pe in other words watts need to push it so in other words you can blow a sub going to big with the sd or over heat the motor by dampening with the sd of the sub.and making the box to small this is were it is either trial and error or buy the soft ware i suggested

what i suggest you check out if designing lines is old colony books on line store they have a soft ware program for t line it like 130 bucks just google old colony book store.

and yes the bass is compareable to a well built ported box so it is basicaly a waste of your time and money to build a box 3-5 times the size of a ported and get about the same output. but ya some people do it just to have fun lol'z like me lol'z :trippy:

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I have saved a little money for some wood, and still have glue, clamps and screws from my other box. I wanted to give building a T-line a try since i have heard fairly good things about them. It's just a for fun box, for my 12" visonik i got a while back. Amp and power and all that is covered, it's going in the house for now (no car til who knows when >.<). it's for music, primarily low notes in rap music. i was gonna try for a tuning of ~27-29hz. Now on to the hard part.

I havent had alot of computer time recently, but in the time i have had, i couldnt find a calculator for a 1/4th wave transmission line. The specs i can give you for my sub: 250rms rated (takes double fine for a couple hours) 8mm xmax between 6"-8" mounting depth, and overall, in every box i've had it performs extremely well for a $20 sub, brand new.

How do i calculate length for the line? Box will be 3/4" mdf. Size Is Not an issue.

Thanks for your answers, looking forward to this project.

Gotta get this done, severe boredom and grounding has landed my poor sub in a cardboard box (took the time to reinforce and deaden the cardboard too ). Sadly it still sounds better than my radio :trippy:

here is line length tLL = 0.25 x c' / fs. were c' is equal; to the speed of sound 13560 so 3390 divied by your fs of the sub. to get t-line length in inches

also these guys are right you do not need a box this big most people use the easy way of doing it so it will fit they will tune it between 48-35 hertz which is 6 to 8 foot how to find were your tuned at is take the strait line down the center of the line and devide by 3390 to get the hertz were the box is going to peak at.it will drop off after this point. a 7 foot long line will play down in the 20 hz range no problem. does not mean it will be loud at 20 hertz

area of the line opening is based on sd of the sub if you go larger you will lose pe in other words watts need to push it so in other words you can blow a sub going to big with the sd or over heat the motor by dampening with the sd of the sub.and making the box to small this is were it is either trial and error or buy the soft ware i suggested

what i suggest you check out if designing lines is old colony books on line store they have a soft ware program for t line it like 130 bucks just google old colony book store.

and yes the bass is compareable to a well built ported box so it is basicaly a waste of your time and money to build a box 3-5 times the size of a ported and get about the same output. but ya some people do it just to have fun lol'z like me lol'z :trippy:

Good read. I have my 6th order BP to bump now anyway, i guess a T-line is for another day.

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I have saved a little money for some wood, and still have glue, clamps and screws from my other box. I wanted to give building a T-line a try since i have heard fairly good things about them. It's just a for fun box, for my 12" visonik i got a while back. Amp and power and all that is covered, it's going in the house for now (no car til who knows when >.<). it's for music, primarily low notes in rap music. i was gonna try for a tuning of ~27-29hz. Now on to the hard part.

I havent had alot of computer time recently, but in the time i have had, i couldnt find a calculator for a 1/4th wave transmission line. The specs i can give you for my sub: 250rms rated (takes double fine for a couple hours) 8mm xmax between 6"-8" mounting depth, and overall, in every box i've had it performs extremely well for a $20 sub, brand new.

How do i calculate length for the line? Box will be 3/4" mdf. Size Is Not an issue.

Thanks for your answers, looking forward to this project.

Gotta get this done, severe boredom and grounding has landed my poor sub in a cardboard box (took the time to reinforce and deaden the cardboard too ). Sadly it still sounds better than my radio :trippy:

here is line length tLL = 0.25 x c' / fs. were c' is equal; to the speed of sound 13560 so 3390 divied by your fs of the sub. to get t-line length in inches

also these guys are right you do not need a box this big most people use the easy way of doing it so it will fit they will tune it between 48-35 hertz which is 6 to 8 foot how to find were your tuned at is take the strait line down the center of the line and devide by 3390 to get the hertz were the box is going to peak at.it will drop off after this point. a 7 foot long line will play down in the 20 hz range no problem. does not mean it will be loud at 20 hertz

area of the line opening is based on sd of the sub if you go larger you will lose pe in other words watts need to push it so in other words you can blow a sub going to big with the sd or over heat the motor by dampening with the sd of the sub.and making the box to small this is were it is either trial and error or buy the soft ware i suggested

what i suggest you check out if designing lines is old colony books on line store they have a soft ware program for t line it like 130 bucks just google old colony book store.

and yes the bass is compareable to a well built ported box so it is basicaly a waste of your time and money to build a box 3-5 times the size of a ported and get about the same output. but ya some people do it just to have fun lol'z like me lol'z :trippy:

Good read. I have my 6th order BP to bump now anyway, i guess a T-line is for another day.

ya port are very much the same out put by increasing ripple in a ported by 3 db's you get about the same out put as a t line but most sq designers try to get rid of the ripple so you get a flat responce. but if looking to bascally double your power you need ripple +3db's same as a tline. so if you know any thing about frequency responce graph you will ripple is listed in bull lock in boxes in these graph of alternitive alignments but if you do not. here are a couple good reads bull lock on boxes is awesome ported info also loud speaker design cook book has it points you can find them chep on amazon .com e bay's half etc.... by increasing ripple you get to use a smaller box then a t line with the same output. just a tip:

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Actually, a port (hemolitz resonator) and a T-line are not even remotely the same.

A port works off of resonance, a T-line is non-resonant.

A port has a tuning, T-line does not have tuning, it has a cut-off determained by physical length, wavelength and stuffing density.

Kind of a big missunderstanding with T-lines....

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Actually, a port (hemolitz resonator) and a T-line are not even remotely the same.

that is correct. to bad i was not comparing them that way but with output which is very much the same. some times less depening on how dampened they are. but this is also depening on the sub and how well it preforms in that box.

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Man why does it have to be like That thought the whole point for this forum is for people to ask question and share knowledge. If you have knowledge be humble and help others And not be so annoyed with them. I'm out.

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Man why does it have to be like That thought the whole point for this forum is for people to ask question and share knowledge. If you have knowledge be humble and help others And not be so annoyed with them. I'm out.

There is a search function and when you use it and reference it in your question you get better answers. Really easy to ask an effective question. Read the OP's other threads, he'll even admit he asks questions way before he is ready. A little history helps.

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Pm me, chris, keep asprin handy.

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Pm me, chris, keep asprin handy.

Need PM because you know you are wrong? Why not post up here?

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Whats up m5, is this place powered4sound yet or what?

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Well cool! We are going to be wrong for bit ok?

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Pm me, chris, keep asprin handy.

:)

I am interested in learning some of the math involved with different box types, and resonance and such. I think, with help of ritalin and diet coke, if i can read it, after a bit of time (and experimentation) i can learn.

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Pm me, chris, keep asprin handy.

:)

I am interested in learning some of the math involved with different box types, and resonance and such. I think, with help of ritalin and diet coke, if i can read it, after a bit of time (and experimentation) i can learn.

If it requires a PM you shouldn't believe any of it...

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