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juanmgarza26
10-15-2013, 04:29 AM
I want to experiment with a t line, I have really no definite answer, perhaps there is none, I know it requires quite a bit of space for a properly designed t line, what exactly are the advantages of a t line?

Jeffdachef
10-15-2013, 04:51 AM
wide bandwidth and great efficiency... IF done right lol.

juanmgarza26
10-15-2013, 04:59 AM
I got a pair of rf p1's and I wanna see how these suckers will do in a t line with low power, I came across t lines and want to experiment with them

black05alti
10-15-2013, 05:19 AM
like jeff said... really, really efficient and wide bandwidth. there's quite a few threads about t lines on diyma

bbeljefe
10-15-2013, 10:29 AM
Another advantage of wave transmission lines is that they're super easy to calculate. Of course, that's offset by the difficulty in designing the box to fit in your vehicle but on balance, I think it's well worth the difficulty.

They play well throughout the sub bass region and normally extend to about one octave below driver Fs before going -3dB... which is super low compared with the response of a conventional ported enclosure tuned in the low 30s.

Drivers with a Qts above 7 and a Qes below 4 are best suited for them but any sub will perform its best in a t-line.

Here are some resources on them:
Transmission Line Speakers (http://www.t-linespeakers.org/)
Quarter Wavelength Loudspeaker Design (http://www.quarter-wave.com/)

Here are a few I've built:
http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/587392-jbl-gto-10-%BC-wave-t-line.html
https://www.youtube.com/watch?v=FN-s4efefZo

UsAmpsFreak
10-15-2013, 11:03 AM
Another advantage of wave transmission lines is that they're super easy to calculate. Of course, that's offset by the difficulty in designing the box to fit in your vehicle but on balance, I think it's well worth the difficulty.

They play well throughout the sub bass region and normally extend to about one octave below driver Fs before going -3dB... which is super low compared with the response of a conventional ported enclosure tuned in the low 30s.

Drivers with a Qts above 7 and a Qes below 4 are best suited for them but any sub will perform its best in a t-line.

Here are some resources on them:
Transmission Line Speakers (http://www.t-linespeakers.org/)
Quarter Wavelength Loudspeaker Design (http://www.quarter-wave.com/)

Here are a few I've built:
http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/587392-jbl-gto-10-%BC-wave-t-line.html
https://www.youtube.com/watch?v=FN-s4efefZo

I've always heard that T-lines usually will give you far and away the highest output, it's just a pain in the *** to build them lol

bbeljefe
10-15-2013, 11:15 AM
I've always heard that T-lines usually will give you far and away the highest output, it's just a pain in the *** to build them lol

Depends on what you mean by build. The actual build process is no more difficult than a properly constructed ported box but, designing them to fit in a vehicle can be a challenge, given that a line for a small sub with an Fs of 30Hz will be about 9' long.

And calculating one can be done with a simple, garden variety calculator... no software needed.

juanmgarza26
10-15-2013, 12:54 PM
Wow the math is really not hard at all, dam a t line for a skar I have laying around would be quite a massive enclosure for one 12

jrdnhsnbrg
10-15-2013, 01:00 PM
I wonder how long a t line for 4 8's would be... Brb gonna go try to figure this out lol

juanmgarza26
10-15-2013, 01:11 PM
Which 8 are we talkin here?

jrdnhsnbrg
10-15-2013, 02:06 PM
Not sure yet, either sundown sa8, IA I series 8, or cadence s2w8.

juanmgarza26
10-15-2013, 03:53 PM
Divide 1120 by the fs of your choice of sub and divide that by 4
(1128/fs)/4 and that will be the length of your t line

jrdnhsnbrg
10-15-2013, 04:32 PM
Divide 1120 by the fs of your choice of sub and divide that by 4
(1128/fs)/4 and that will be the length of your t line

I'm getting 8.09 feet, would it make a difference with 4 subs over 1?

Dub7sonoma
10-15-2013, 04:39 PM
I'm getting 8.09 feet, would it make a difference with 4 subs over 1?

No. The length stays the same. Your line volume will be x4. The length of the line has to do with the fs of the sub. The diameter of the line increases with more cone area

des343
10-15-2013, 04:48 PM
can you sacrifice length for depth in any way? and i see the 8 inch type r has a T-line box alpine created for it..i heard amazing things of that type r in that box..

Dub7sonoma
10-15-2013, 04:50 PM
Now measure from the middle of the surround on one side of your sub to the middle of the surround on the opposite side. That will give you your cone diameter. It will probably be around 6.5". Divide that in half to get the radius of the cone =3.25". Now use π r2 = which gives you roughly 33 square inches for 1 8" sub. You are wanting to do 4 8" subs.... So you will need a line volume of 132 square inches.

Dub7sonoma
10-15-2013, 04:51 PM
No you cant sacrifice the length

Dub7sonoma
10-15-2013, 04:53 PM
I built a t-line for my wifes Jimmy with 2 DD2508 and its crazy loud for 2 8s. 4 8s should be amazing

des343
10-15-2013, 04:54 PM
No you cant sacrifice the length
guess ill never be seeing a tline then lol i dont know of a vehicle that is wide enough to consider it properly

jrdnhsnbrg
10-15-2013, 05:27 PM
So I'd need an 8.09' box with port dimensions of 12"x11" or something similar... interesting.

juanmgarza26
10-15-2013, 10:52 PM
I made a design for the p1 I'll start it this weekend and see how she turns out, I have no way of metering but I'm hoping to be impressed by a 150 rms 10

UsAmpsFreak
10-15-2013, 11:16 PM
Another advantage of wave transmission lines is that they're super easy to calculate. Of course, that's offset by the difficulty in designing the box to fit in your vehicle but on balance, I think it's well worth the difficulty.

They play well throughout the sub bass region and normally extend to about one octave below driver Fs before going -3dB... which is super low compared with the response of a conventional ported enclosure tuned in the low 30s.

Drivers with a Qts above 7 and a Qes below 4 are best suited for them but any sub will perform its best in a t-line.

Here are some resources on them:
Transmission Line Speakers (http://www.t-linespeakers.org/)
Quarter Wavelength Loudspeaker Design (http://www.quarter-wave.com/)

Here are a few I've built:
http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/587392-jbl-gto-10-%BC-wave-t-line.html
https://www.youtube.com/watch?v=FN-s4efefZo

Hey dude, nice to meet you. I'm an experienced installer of 15 years, just getting back into the car audio realm after a few years away and looking to put a pretty hardcore demo system back into my vehicle. It's gonna be in a Chevy Silverado with a camper shell and pulling the rear window. Might want to look into doing a tline in it as i've never done one. Any help/advice you can give me would be awesome. PM me if you want and thanks for any help you can give.

bbeljefe
10-16-2013, 12:17 AM
Hey dude, nice to meet you. I'm an experienced installer of 15 years, just getting back into the car audio realm after a few years away and looking to put a pretty hardcore demo system back into my vehicle. It's gonna be in a Chevy Silverado with a camper shell and pulling the rear window. Might want to look into doing a tline in it as i've never done one. Any help/advice you can give me would be awesome. PM me if you want and thanks for any help you can give.

Nice to meet you too. I'm in about the same boat except that I took a car audio break for about 20 years. Did commercial and residential sound, home theater, video, telecom, data, security, fire detection et al in the interim but never lost my love for car audio, so I decided to seriously re-enter the hobby about a year ago and now that has turned into me opening a shop. :-)

UsAmpsFreak
10-16-2013, 12:41 AM
Nice to meet you too. I'm in about the same boat except that I took a car audio break for about 20 years. Did commercial and residential sound, home theater, video, telecom, data, security, fire detection et al in the interim but never lost my love for car audio, so I decided to seriously re-enter the hobby about a year ago and now that has turned into me opening a shop. :-)

Ha ha, very cool. I thought about opening a shop but never took the plunge. Good luck to you.

bbeljefe
10-16-2013, 12:47 AM
Ha ha, very cool. I thought about opening a shop but never took the plunge. Good luck to you.

Thanks. I figure this will be the only way I can finish out what working life I have left doing something I love. :-)

UsAmpsFreak
10-16-2013, 12:48 AM
Thanks. I figure this will be the only way I can finish out what working life I have left doing something I love. :-)

That's cool man, where you located at?

bbeljefe
10-16-2013, 12:53 AM
I'm in my office right now but I'm about to head to bed.

And those are in Shreveport.

UsAmpsFreak
10-16-2013, 12:56 AM
I'm in my office right now but I'm about to head to bed.

And those are in Shreveport.

Ah, pretty cool, same side of the states as me. I'm in Pensacola, FL