15" T-Line sub box?

[CHEVY4X4BLAZER]

I'm curious about a t-line for my sub, truck bit I don't think I have enough room. :/

[kandiman71874]

Have fun with it.

The port is actually 11" not 10.75. Never did correct that and rescan it.

Quite a few people around Kansas City have heard this box. Its a great design for something like a DC Lvl 4. Extra spider and LVL 5 coil were the options i had on mine and what is currently in it with its new owner with 1000 rms on it.

[87regal]

The 1/4 wave tutorial I wrote on this thread is a " Quarterwave for Dummies" type thread. Unless you plan on doing Tlines in home audio, the basic formula works 100%. Reason I posted that thread up was to 1/4 wave idea is not as hard as people like Martin King shows it to be with their mathematical formula. If you want to waist your time on that or other formulas which have almost no use in a car, go ahead. But I've tested and built over 100 Tlines in my days. When I realized the formulas were not intended for car, I knew there had to be something easier. So in car testing due to a compressed environment that the very basics are only needed to calculate a tline. Infact that you can make Universal prefab Tlines and throw almost any sub in them. As long as its in a car not a house. When I worked at the last shop I worked at, every customer that wanted just one sub, he got a prefab tline that I would keep on the sales floor. Tuned to 40hz not a single sub or box ever came back. So that is why I typed that thread up, just to show tlines really are not as complicated as most thinky

Although this generic approach might yield acceptable results, if I would have used it my design would have ended up being about 30% larger with many more cuts...not to mention a headache to fit the magnet.

I'm not trying to knock the tutorial, it's really great for what it is...but IMO if someone is putting together a serious project they might be better off doing some additional research.

That being said, I'm looking forward to any future updates, thanks for sharing your knowledge.

[Forevrbumpn]

Your definitely right. As I said its a simple approach to it. Personally when I do Tlines my lines are not consistent. I start my lines off tight and go up for full sd or larger. Similar to a horn. Then I try and match line area with vas of woofer. My personally used technique to a tline uses moderate Vas sub higher Fs 30-40hz . Line area is based on vas Fs. So when a 15"can has a 5-6cf vas and a Fs around 35 hz. I know its a perfect match for a reasonable sized tline. As far as magnets depth of line that's where you need to design it to suite. A chamber? A notch behind the woofer? Magnet out?

There is also my favorite tline design which is a 4th order tline. There is 6th order passive radiators tapered in and out. Ive designed and tested all these designs. And like the vas method not mentioned in the thread.

[87regal]

Your definitely right. As I said its a simple approach to it. Personally when I do Tlines my lines are not consistent. I start my lines off tight and go up for full sd or larger. Similar to a horn. Then I try and match line area with vas of woofer. My personally used technique to a tline uses moderate Vas sub higher Fs 30-40hz . Line area is based on vas Fs. So when a 15"can has a 5-6cf vas and a Fs around 35 hz. I know its a perfect match for a reasonable sized tline. As far as magnets depth of line that's where you need to design it to suite. A chamber? A notch behind the woofer? Magnet out?

There is also my favorite tline design which is a 4th order tline. There is 6th order passive radiators tapered in and out. Ive designed and tested all these designs. And like the vas method not mentioned in the thread.

Now that's the kind of stuff I'd love to see! What is the deal with figuring compression chambers into the design? Do you have a method for estimating response curves?

[EMD Enclosures]

Do u have the sketchup of your "universal" design? If so, I'd be really interested in seeing it if its not too much of a hassle

[bred904]

Your definitely right. As I said its a simple approach to it. Personally when I do Tlines my lines are not consistent. I start my lines off tight and go up for full sd or larger. Similar to a horn. Then I try and match line area with vas of woofer. My personally used technique to a tline uses moderate Vas sub higher Fs 30-40hz . Line area is based on vas Fs. So when a 15"can has a 5-6cf vas and a Fs around 35 hz. I know its a perfect match for a reasonable sized tline. As far as magnets depth of line that's where you need to design it to suite. A chamber? A notch behind the woofer? Magnet out?

There is also my favorite tline design which is a 4th order tline. There is 6th order passive radiators tapered in and out. Ive designed and tested all these designs. And like the vas method not mentioned in the thread.

so if a mmats juggernaut 15" sub has a vas of 3.6ft3 and a f0 of 36hz then it should be a nice sub for a t'line?

[EMD Enclosures]

Did u still have that "universal" design? Id be interested in maybe seeing it if its not too much of a hassle

[Forevrbumpn]

I can draw one up. Its similar to Kandis . Just 140sqinch port 40hz long for a 15"ends up around 39"*19"*20" if I remember right. But when I say universal, I just think 40hz for any subs from 8"-15" and just average a area. 140" fifteen, 80" twelve, 55-60" ten inch, 35-40" 8" sub. I have never made a crappy sounding tline using that super simple beginners idea.

[Forevrbumpn]

When I get to a computer I will look for my olllddd photobucket acct that has a bandpass compound iso universal tline I built to do ultimate testing. One box, standard 35hz tline, bandpass tline peaking around 42, compound tline-2-15" peaking around 32-34hz and a choked tline. 4 designs one transforming box.