T-Line SQ

[Weigel21]

Wonder if a 15" sub would even be something one would consider for a T-Line enclosure. Only ask as that seems to be the only sub I have just lying around without an enclosure.

I've got a polk MM1540, which has a QTS of .5, FS of 27Hz and VAS of 3.5cuft.

Sorry, those looked like the only specs talked about in the reading I did, but the rest of the T/S Parameters can be found here.

So I wonder if that sub would even be worth attempting a T-Line enclosure for.

Guess the only other sub I have they "d probably look to mess with building a T-Line enclosure for is an old Optimus sub from Radio Shack. Picked up the sub about five years ago brand new, put it in a sealed enclosure and loaned it to a friend for a few months. I did the install, set the gain, etc etc, and I know the sub was never pushed hard, hell, it may have just finally gotten broken in by the time T got it back. Anyways it's a PRO-CSW800 *' sub.

Specs for it, QTS .57, FS 45.1Hz, VAS .77cuft.

Not sure I can find full T/S Parameters online to link to, but I have the owners manual if you need more specs. Then again, it's not designed to take a lot of power, so it may well prove to be kinda weak.

[Krakin]

Also don't look to give full RMS to a T-line enclosure. With it being the way it is the mechanical handling is much lower.

[NathanW]

I'll have to get the photo my friend took of the inside of the box before I put the top on it so I can post it here. The best I can do is post a picture of the sketchup design I made of it before building the box but for some reason the image box here keeps locking up and won't let me post anything.

I can however describe the box. It's 29" w 13" h 28.75" d (external), the line is 11.5" x 6.25" x 9.43 ft. folded four times. The internal corners and edges are all rounded with 12" concrete forming tube cut to size and 3/4 round overs. The space between the forming tubes and walls of the box is filled with expanding foam insulation.

[NathanW]

Err, double post...

[Weigel21]

Not quite as large as I thought it'd be.

[White Lightning]

In all honnestly guys ... If you are going "full Sound Quality" here ...

For the time and work it would take to build and integrate a T-line enclosure into a Sound Quality vehicle ... You could do SOOO much more in your front stage and image with using a well built basic ported and tuned enclosure. Really guys, sub bass is only 15% at best when it comes to true Sound Quality.

If you can build a front stage setup good enough .... You wouldn't even need a sub stage.

... Which is what I plan to do with my 49 Ford Project.

[Krakin]

Sealed is the easiest for getting a basic curve, ported allows more control.

There just seems to be so much with a TL that it's not worth it imo.

Fun, yes, but not worth it unless you want something different and you feel like learning all about them.

[NathanW]

I have to disagree with sub bass being only 15% at best to true SQ. While you are correct in a more literal way, I have to say that a well integrated low end is just as important as any other part of a SQ system. Whether it comes from a large subwoofer or smaller sub/woofers in the front of the vehicle, if it doesn't blend right with the rest of the sound it ruins the system.

And as for T-Lines being too complicated to design and build, they are actually very easy to design, and if you can build a bandpass box you can build a T-Line.

To each their own, I just hope some of you give a T-Line a try for yourself before deciding it's not really worth it.

[White Lightning]

I have to disagree with sub bass being only 15% at best to true SQ. While you are correct in a more literal way, I have to say that a well integrated low end is just as important as any other part of a SQ system. Whether it comes from a large subwoofer or smaller sub/woofers in the front of the vehicle, if it doesn't blend right with the rest of the sound it ruins the system.

I was more or less referring to vehicle prep .. meaning power source, wiring, deadning and anything else that needs to be done before system installation.

Then we go into first and formost Sound Stage and Imaging. And yes, sub bass plays a MAJOR part here just as much as front stage.

Then there is testing and tuning, Equalization, time alignment and music selection ...

And above all this ... work on attention to details and "WOW" factors. This includes the vehicle just as well as system build.

MOST people in car audio today (including some in Sound Quality) have no idea that you need to time align your sub bass to match up with the front stage and image ... All they worry about is making mids and highs keep up with the bass ...

So while I'm making up my "things to do" list on my 49 Ford Sound Quality project ... adding Sub Bass just hasn't made in on the list yet.

When you actually factor EVERYTHING that needs to be done to a Sound Quality vehicle before competition ... Sorry but I feel that MASSIVE Sub Bass (while as you say is true ... Very Important when blending the entire system for a natural environment sound) is not at a high priority on the list ...

[IH8PunkRok]

I run a tline and honestly I don't think it works well in an sq application. Reason being it has a stupid cut off at the drivers fs and it doesn't have a very flat output curve. Don't get me wrong I love mine but I can see why they aren't used all that much in real sq stuff