transmission line port box

[lorideslo 10+ year member]

Don't know anything about this box. A manager at a local audio shop says its the best of both worlds between a sealed and ported box. He also said its a custom box, that takes more time to build than a ported box. I wanna know is it the best of both between sealed and ported? What are the pros and cons of the transmission line box?

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[SVT03L 10+ year member]

Read up http://quarter-wave.com/

I wouldnt say its better then a sealed or ported box. It all depends on what your looking for. Its a little more complicated to build too. I would stick with a well designed ported box.

 

[itssteve 10+ year member]

i wanna know what local shop i am in that area right now and i know most of the shops dont know much about custom enclosers

 

[Immacomputer 10+ year member]

I agree with SVT -- It's not the best of both worlds for some people but for some it is. There is no best enclosure out there, only what is right for the vehicle and customer.

I run a transmission line enclosure with my sub and for my musical tastes, it's perfect but some people may want something different. Transmission lines lead to a more natural sound of the driver (similar to sealed or infinite baffle alignments) with the extra output and cone control around the system resonance like in a ported enclosure.

The biggest drawback to transmission lines is that many people try to design them based around the sub and only the sub. In a home environment, this is acceptable due to room gain being easier to deal with than cabin gain. In a car environment, the enclosure needs to be designed more with the car in mind than with the driver. Many people just look at Fs and Sd to get the line area and line length and the vehicle is left out of the equation. This leads to a poor design that may work out well or may blow ***.

I would be weary of any shop that wants to build me a transmission line enclosure unless they make the design based more around the car than the sub. You should ask them what they use to design the enclosures and what they factor in. If they say only something about the sub and it's parameter and make no mention of the vehicle and your listening preferences, I would kindly tell them that you would like something different.

 

[lorideslo 10+ year member]

i wanna know what local shop i am in that area right now and i know most of the shops dont know much about custom enclosers

Goho audio....

 

[lorideslo 10+ year member]

I agree with SVT -- It's not the best of both worlds for some people but for some it is. There is no best enclosure out there, only what is right for the vehicle and customer.
I run a transmission line enclosure with my sub and for my musical tastes, it's perfect but some people may want something different. Transmission lines lead to a more natural sound of the driver (similar to sealed or infinite baffle alignments) with the extra output and cone control around the system resonance like in a ported enclosure.

The biggest drawback to transmission lines is that many people try to design them based around the sub and only the sub. In a home environment, this is acceptable due to room gain being easier to deal with than cabin gain. In a car environment, the enclosure needs to be designed more with the car in mind than with the driver. Many people just look at Fs and Sd to get the line area and line length and the vehicle is left out of the equation. This leads to a poor design that may work out well or may blow ***.

I would be weary of any shop that wants to build me a transmission line enclosure unless they make the design based more around the car than the sub. You should ask them what they use to design the enclosures and what they factor in. If they say only something about the sub and it's parameter and make no mention of the vehicle and your listening preferences, I would kindly tell them that you would like something different.

What's your music taste? Mine is wide I like mostly rap and r&b but I also like oldies, jazz and rock. Would ***** line box be good for my music taste? It would be goin in the trunk of a 90 cad deville.

 

[Immacomputer 10+ year member]

Hmm... I don't think a transmission line would go well with your vehicle. With a transmission line, you want to effectively couple the enclosure to the air mass of the vehicle. The best way to do that, is for the cabin to either have a slightly increasing cabin cross sectional area (like a hatchback) or a consistent area (like an SUV). That helps give you an even longer line length than the original enclosure and will have nice output at the front of the vehicle (mouth of the line). With a vehicle like yours, you're better off with a standard ported enclosure or using a bandpass system to couple into the cabin. Basically, in trunk cars, you need the trunk to act as part of the enclosure to pressurize the cabin. Transmission lines aren't really cut out for this type of energy transfer.

In my car though ('99 Integra hatch), the car acts as part of the line and so I have a very large line length and can get very nice low frequency extension. My preference in sound is tight bass with flat low frequency extension down to at least 20hz and up to about 70hz. I listen to all kinds of music ranging from classic rock, to break beats, to ambient sounds (NASA's voyager recordings, nature recordings, etc.) to rap to opera and pretty much anything else that I "feel" when I listen to it. I like the sub to be natural and not bloated sounding with very little stored energy. The transmission line works much better for me than sealed boxes have and much better than ported boxes have. It has far more low end than either with the overdamped sound of a large sealed enclosure. This sound type will vary with different subs in but the final frequency response will stay relatively the same as long as the parameters aren't too extreme in the Q of the driver.

I also run a transmission line in my room with a higher Q driver and the sound is slightly different. It is still natural sounding but with a little more "lazy" or laid back sound to it. The low to mid Q drivers will give more of a tight and punchy sound in a transmission line while a higher Q driver will tend to be more laid back.

Your best bet is to try to listen to one of their transmission lines in a trunk vehicle that is similar in size and shape to yours. If you like the sound, you will probably be happy with one in your car, if not, ask for something different. My understanding of transmission lines and my ideas of coupling the enclosure to the cabin of the vehicle just don't like the idea of using one in a trunk car like that. I could very well be wrong though.

 

[lorideslo 10+ year member]

Hmm... I don't think a transmission line would go well with your vehicle. With a transmission line, you want to effectively couple the enclosure to the air mass of the vehicle. The best way to do that, is for the cabin to either have a slightly increasing cabin cross sectional area (like a hatchback) or a consistent area (like an SUV). That helps give you an even longer line length than the original enclosure and will have nice output at the front of the vehicle (mouth of the line). With a vehicle like yours, you're better off with a standard ported enclosure or using a bandpass system to couple into the cabin. Basically, in trunk cars, you need the trunk to act as part of the enclosure to pressurize the cabin. Transmission lines aren't really cut out for this type of energy transfer.
In my car though ('99 Integra hatch), the car acts as part of the line and so I have a very large line length and can get very nice low frequency extension. My preference in sound is tight bass with flat low frequency extension down to at least 20hz and up to about 70hz. I listen to all kinds of music ranging from classic rock, to break beats, to ambient sounds (NASA's voyager recordings, nature recordings, etc.) to rap to opera and pretty much anything else that I "feel" when I listen to it. I like the sub to be natural and not bloated sounding with very little stored energy. The transmission line works much better for me than sealed boxes have and much better than ported boxes have. It has far more low end than either with the overdamped sound of a large sealed enclosure. This sound type will vary with different subs in but the final frequency response will stay relatively the same as long as the parameters aren't too extreme in the Q of the driver.

I also run a transmission line in my room with a higher Q driver and the sound is slightly different. It is still natural sounding but with a little more "lazy" or laid back sound to it. The low to mid Q drivers will give more of a tight and punchy sound in a transmission line while a higher Q driver will tend to be more laid back.

Your best bet is to try to listen to one of their transmission lines in a trunk vehicle that is similar in size and shape to yours. If you like the sound, you will probably be happy with one in your car, if not, ask for something different. My understanding of transmission lines and my ideas of coupling the enclosure to the cabin of the vehicle just don't like the idea of using one in a trunk car like that. I could very well be wrong though.

Thanks man, but I'm goin to pass on that box. I think I'm goin to get a sealed box.

 

[lorideslo 10+ year member]

Basically, in trunk cars, you need the trunk to act as part of the enclosure to pressurize the cabin.

My cousin says the same thing. He also says that ported boxes are better for SUVs and hatchbacks b/c of all the open space the air can flow from the front seat to the back where the sub is. And he says since the trunk acts as a enclosure that I should get a sealed box. DO YOU AGREE? I want that boom but I don't want the bass to over power the other sounds in a song. What do you think?

This will be my 1st system if you can't tell

 

[Immacomputer 10+ year member]

Well, I agree for the most part, but ported enclosures are not like transmission line enclosures as far as how they manipulate the rear wave of the sub. A ported box will use a port to act like another sub around the tuning frequency giving you more output around there. Ported enclosures can work great in trunks and are not only meant for hatches and SUVs.

If you want the sub to blend well with the other speakers, you either go sealed or ported (so long as you tune low enough to avoid any nasty peaks and loss of low frequency extension) and in the end, that blending is going to depend on your level setting and the midbass extension of your front speakers.

 

[lorideslo 10+ year member]

Well, I agree for the most part, but ported enclosures are not like transmission line enclosures as far as how they manipulate the rear wave of the sub. A ported box will use a port to act like another sub around the tuning frequency giving you more output around there. Ported enclosures can work great in trunks and are not only meant for hatches and SUVs.
If you want the sub to blend well with the other speakers, you either go sealed or ported (so long as you tune low enough to avoid any nasty peaks and loss of low frequency extension) and in the end, that blending is going to depend on your level setting and the midbass extension of your front speakers.

Thanks man.....I'm still leanin toward sealed tho...

 

[302yota 10+ year member]

any pics of this type of enclosure?

 

[shaneb 10+ year member]

any pics of this type of enclosure?

http://images.google.com/images?um=1&hl=en&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&q=transmission+line+enclosure&btnG=Search+Images

 

[302yota 10+ year member]

those enclosures are crazy...good luck with all that