T-Line Enclosures

[bunkerking09 10+ year member]

Can someone explain these to me?

I tried the search button, didn't get anything.

Click to read more...

 

[Rashaddd 5,000+ posts]

Its essentially a long 'port' with an area = to cone area, and the length is = to the quarter wave length of the frequency you want it tuned to. There is no 'net volume' in the sense of a ported box, in a t-line, just 'port'.

If you need one designed, pm me for a quote.

 

[bunkerking09 10+ year member]

how does the port area = the cone area? I think I understand the wavelength thing...but the other is throwing me for a lupe.

can it be used for a daily box and not just a burp box for a certain frequency? //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[slam 5,000+ posts]

The line area should equal or exceed slighty the cone area of the driver used. Normally, it is difficult to make the line area exactly equal to the cone area, as the frame and mounting immediately force an area larger than the cone area. The area can be gradually tapered down to the actual area to save space, but it can remain the same as when it started, as long as it is not more than than about 20-25% more area. This means a very tight sizing for the woofer mount and the begining of the line.

 

[Rashaddd 5,000+ posts]

how does the port area = the cone area? I think I understand the wavelength thing...but the other is throwing me for a lupe.
can it be used for a daily box and not just a burp box for a certain frequency? //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

Lets say for example your cone area = 100 sq in. you'd then need the area of the t-line to = 100 sq in along the whole length of the line (like a port area of 100 sq in)

In terms of response, it will be affected by your car and your sub, but they have close to an 'ideal' bandpass response generally in terms of output. They are meant (typically) to extend an octave or so below tuning without the loss of output you see with regular ported boxes, as well as plenty above tuning, for a very flat response.

 

[rollerdj 10+ year member]

please expain the quarter wave length a little more. That's got me a little perplexed. //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[Rashaddd 5,000+ posts]

To tune it to a full wave length, you'd just use the length of a wave of that frequency. Divide that by 4 and you have your quarter wave length.

 

[Immacomputer 10+ year member]

(Speed of sound in inches/second) / (4*Frequency in hz) = wavelength in inches

Transmission line enclosures do not always need to have the line area equal to the cone area nor does it always need to exceed it. This can work but is often not necessary. In order to find out how much line area you need, you need to consider the resistance factor of the driver, the shape function of the line (line taper and line frequency), the Sd, and the Re/(BL^2) product. That will give you an idea of how much line area would be optimal for the driver. Changing the line taper and line area will affect the frequency response and low frequency extension of the system. If the line area is too small for the mounting depth of the driver, it's possible to add a compression chamber for the speaker to fit.

Transmission line enclosures don't have to be as large as people think. I fit one in smaller dimensions than I fit a 2.2 cube ported enclosure. It had better efficiency; low frequency extension; power handling (mechanical power handling increased around 15-25hz); and transient response.

They are not going to be the best for getting loud at a single frequency but will offer a very musical and very efficient enclosure with a low end that is effortless and full. That is if the design is well implemented for the driver and vehicle.

 

[wasted ink 10+ year member]

http://www.stevemeadedesigns.com/board/index.php?showtopic=1828

 

[Immacomputer 10+ year member]

That's a bad tutorial.

 

[IDSkoT 5,000+ posts]

That's a bad tutorial.

You should write one up. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

p.s. where've you been?

You seem to be the only knowledgeable one in this whole site.

 

[ahillworks 10+ year member]

http://www.stevemeadedesigns.com/board/index.php?showtopic=1828

Very Very nice! Good one. This should be typed up and posted in the stickies.

 

[wasted ink 10+ year member]

That's a bad tutorial.

Write a better one then.

 

[SVT03L 10+ year member]

Write a better one then.

Here is a better one quarter-wave.com

 

[wasted ink 10+ year member]

problem solved //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

that is a good one