Simple document for building Transmission Lines?

[enigmaticEntity.]

I was wondering if it would be worth trying to build TL enclosures for my full ranges (when I get some)?

Could it be as simple as:

- Choosing a (1/4 wave) line length just below Fs;
- Designing a tapered, labyrinth line that fits inside the desired enclosure shape;
- Finding the cross sectional area;
- Having to adjust the line length for stuffing?

Would I be able to do this without going through such detail as I find on most of the websites I look at?

(Sorry, I don't really understand the math, just that the 1/4 wave, stuffing and tapered line helps reduce resonance and give lower bass output.)

Otherwise I may have to settle for a stuffed, deadened ported enclosure.

[planet10]

Simple answer is NO.

What you have described is classic TL design... http://t-linespeakers.org/design/classic.html

1/ you will get less bass if you tune a tapered or straight TL below Fs.
2/ a line that tapers such that the terminus cross-section is smaller than the start needs to be shortened
3/ damping has no effect on the length of the line (see 2)

You will be much further ahead just plugging a driver into Martin King's free alignment tables (available as a downloadable spreadsheet)

dave

[enigmaticEntity.]

Thank you very much.

Just one question: "put the driver on the side of the line"

Does this mean that when I look at the driver from the front, I can see the folds of the TL (if the "side" of the enclosure was taken off)?

[901Fixer]

What FullRange drivers are you building an enclosure for? You may wanna see what someone here has figured out for them already. Some FR drivers will perform much better in a certain design and just ok in a simple sealed or OB. Some will not perform much better in a complicated design. Many fantastic enclosures have been designed here for Fostex FR drivers and it is a shame to put them in anything less.

[loninappleton]

If you haven't gotten your speakers yet, the best TL suggestion I can think of is the Alpha TL in the short article of a now dated issue of Speakerbuilder. Someone may know of a place which has it in another format. Measurements are given for the Jordan 92s.

What I was curious about is the mention of tables for Martin King's calculations that you could plug in values for that is downloadable at no cost. Can someone say more about that? I'm aware of Martin's page for subscribers but not the alignment tables.

[rjbond3rd]

Hi Lon, check out the alignment tables here: http://www.quarter-wave.com/TLs/TL_Theory.html

They are for classic TL's (straight, expanding, tapered) with one end open, as opposed to MLTL's (with the port).

[planet10]

Top 2 links in the bottom section:

http://www.quarter-wave.com/TLs/TL_Theory.html

dave

[loninappleton]

Ok. I get muddled with theory. Is this similar or the same as Rick's Alpha TL then?

That would seem ideal for this thread.

[planet10]

Much more comprehensive than alpha TL.

dave

[loninappleton]

I had a successful load of the TL spreadsheet in Open Office Spreadsheet. Compatibility with free software is a big plus.