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Transmission Lines

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So for the past week i been researching about t-lines and how i can design my own , but so far im just lost . i want to build a t-line for an old rf punch z 10, this is a home project. 

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i know how to get the length of the port and i know how to get the sq inches for the port area , but the thing i dont understand is how do i get the height and width measurements of the port itself

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Transmission line enclosures have no enclosure volume, everything behind the driver is the port.

 

The Loudspeaker Cookbook has a section on them--IIRC.

Edited by ssh

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Transmission line enclosures have no enclosure volume, everything behind the driver is the port.

The Loudspeaker Cookbook has a section on them--IIRC.

It does it's just vague. It does reference another book specifically on tlines.

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Not sure where you've read, but if you aren't following that part of Martin King's description then perhaps that is a sign that you should try something else.

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Read Martin King's white paper like Sean said, will help a lot...

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I would try and reach out to pwk designs if he is still around. He is a horny kinda dude lol, meaning if it has a horn type enclosure then he knows how to

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Most of the Transmission Lines you see in car audio actually aren't...  they are normally just 4th order alignments with lots of vent area or a bandpass/horn.

 

Transmission Lines don't have ports that resonate and don't have enclosure volume.  What they do have is a dampened line.  The reason why you don't see many is that they are just too big.  They have to be around 6' long if you want to get near 30Hz and the line has roughly the same cross-sectional area as the driver Sd...  So a 6' line for a pair of 12s ends up being at least as big as an 8-10ft3 "normal" enclosure...

 

And here is the kicker, a Transmission Line's output capability lies in between a standard sealed enclosure and a standard 4th order vented enclosure...  There are some benefits, but they normally don't out-weigh the size and design/testing requirements...

 

If I had a single 8" or 10" woofer and unlimited space, I might consider a Transmission Line... Might...

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Not in a car you wouldn't

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He did say this was a home audio project >.>

But for real, i'm not sure you're choosing this for the right reason, can you elaborate a little on why you think a t-line is what will accomplish your goals?

Trying new things is awesome, but without understanding what it is you're undertaking, it can quickly go from exciting to overwhelming and frustrating.

*I speak from experience.

Edited by SpeakerBoy

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The "new" thing to try would be to design a real enclosure instead of crap

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If you could build something that outperforms this design for a fraction of the cost, materials and time, wouldn't that be a plus? Much simpler, and much more forgiving.

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If you could build something that outperforms this design for a fraction of the cost, materials and time, wouldn't that be a plus? Much simpler, and much more forgiving.

ie ,a standard ported enclosure.  Ding, ding, ding, we have a winner!!

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Lol, thought you were trying to do this a car.

 

For home, get a 6-7' piece of 10" sonotube and mount the driver in one end and loosely fill the whole thing with polyfill or fiberglass (loose kind) and leave the last foot or so barely stuffed.  Mount it vertical and the stuffing will stay in place better.  Use something to keep it (stuffing) off the motor structure.  Mess with the stuffing density to get it to sound right...

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