2 Q 18's in a t-line

[jimbo 0]

Would it be possible to make a transmission line box for 2 18 Q's in an area that's 16" tall x 39" wide x 70" long with an additional area of 22" tall x 52" wide x 10" deep OD?

Like this:

Would having the subs mounted off center make it not work?

Edited May 7, 2008 by jimbo

[JimJ 11]

Not in something smaller than a full-size cargo van, and even then a true TL for 2 18's would be pushing it.

[dem beats 1,223]

how sweet that would be....

[JimJ 11]

Believe me, the thought's crossed my mind

[jimbo 0]

One can only dream.

How about a couple 15's or 12's? Hell, I'll extend my truck bed if I need to. Or even cut out the entire rear glass, and double the height of the box if I have to

[Brassler07 0]

That is going to be a MASSIVE box. I designed a T-line for my 15" 5200 and it was 8.5 cubes gross.

[jimbo 0]

I have around 30 cubes to play around with. I can make more room than that without massive modifications. If it comes down to it I can double that space.

[Brassler07 0]

Wow, you definitely have A LOT of room. That setup will rattle your brain for sure! Imagine a couple of 15" RL-S in a t-line!

[JimJ 11]

30 cubes, I have more than that

What are you trying to accomplish here? While I'm a huge fan of TQWT's for home use, in a vehicle for subbass there are better alternatives on either end of the SQ or SPL spectrum...

[jimbo 0]

I'm looking for all out SQ, with a decent level of subbass output. I really just wanted to do some type of quarter wavelength design, both to have something different, and to see if I can do it. Feel free to give me some suggestions, I'm open to any ideas, as difficult and inconvenient as they may be. All I want is a great sounding substage with a couple of 18" Q's. Output level really means nothing, as long as there are gains in SQ.

That 30 cubes is below the window line. I'll see what I have to work with if I were to wall it off.

EDIT: 44 cubes with a normal wall and a cut through, 48 with a wedge wall, and if it comes down to it, 71 cubes if I do a full cut through and put a tonneau cover on my bed.

Edited May 9, 2008 by jimbo

[JimJ 11]

Go sealed. Two 18's in a low Qtc sealed enclosure will mean that the subs will barely have to move at all to get enough output for you...and you won't have any problem fitting them in.

[audio-neon 34]

and I was gonna suggest an infinite baffle blowthrough.

[jimbo 0]

What do you think about an IB setup?

If I go the sealed route, should I use a larger box with one SAZ-1500 or a smaller box with two strapped? How much power do they need to run IB?

[jimbo 0]

and I was gonna suggest an infinite baffle blowthrough.

Beat me to it. That's what I've been thinking of doing, but I'm having trouble thinking of a way to protect the drivers from the elements.

[///M5 2,833]

Sealed or IB are your choices if you ask me.

[JimJ 11]

In a proper blowthrough, no part of the enclosure or cabin is exposed to the outside...

That'd be a cool idea, but I wouldn't try it in anything short of a dedicated competition vehicle. Simply not worth it for something that gets driven on a regular basis.

[audio-neon 34]

You build a box like normal extending out to the bed I would try to keep bottom at least 4" higher than the bed. But leave the bottom off. Basically you have a top, side and back of a box but with no bottom.

[jimbo 0]

In a proper blowthrough, no part of the enclosure or cabin is exposed to the outside...

That'd be a cool idea, but I wouldn't try it in anything short of a dedicated competition vehicle. Simply not worth it for something that gets driven on a regular basis.

The cabin won't be exposed, what I'm trying to say is how could I go about doing a true IB setup, not a trunk IB type thing, without having the drivers exposed? I'm thinking that I need to get a normal bed cover and seal up all the gaps in the bed. Got any other ideas?

What makes you say that? I almost never use my bed because it's so small, and I have a trailer that I use when I need it. It won't really take up any space in the cab either. Plus, I'm never going to sell it so I dont have worry about resale.

You build a box like normal extending out to the bed I would try to keep bottom at least 4" higher than the bed. But leave the bottom off. Basically you have a top, side and back of a box but with no bottom.

I was thinking about something like that, but it seems like it would restrict the airflow a good amount. I'm thinking the bed cover idea might work best. Opinions?

Edited May 9, 2008 by jimbo

[JimJ 11]

If you're talking about a tonneau cover, I wouldn't see a problem with it, when you said "wall" I was thinking of a full bed cap with no rearward visibility, which would be a big problem

[jimbo 0]

If you're talking about a tonneau cover, I wouldn't see a problem with it, when you said "wall" I was thinking of a full bed cap with no rearward visibility, which would be a big problem

I was thinking about a wall but I think an infinite baffle will work much better. Should I just run the one 1500 at .5 ohms or a 1500 on each driver?

[JimJ 11]

You probably won't even need a kW per driver...

[jimbo 0]

That's what I thought. I'll just stick with the one 1500.

Thanks for the help, looks like I'll be doing an IB blowthrough.

[helotaxi 46]

And I'd probably run that 1500 at 2 ohms. Won't void the warranty and will give you plenty of power for an IB setup.