my box design

it seems like its been forever since I've been on here, i used to be on the forum every day but that was 2 years ago. I'm still into car audio very much and just wanted to say hey.



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Oh Man Theres Troy

And what are you asking about, mentioning, or commenting on? That appears to be a standard transmission-line. Are the red zig-zags representing stuffing, or are they the "path" that the sound takes (supposedly)? If this is what you think is happening, it's not. At subwoofer frequencies, the wavelength is SO long, compared to the "channel" you are directing them down, that it is simply a wave, that will travel in and out of the "terminus". (The end is called the terminus in a TL) There will be no sound wave "bouncing".

Nothing terribly special at all about that enclosure, however, if you choose the proper woofer, you will get tremendous deep, powerful bass, with little or no booming or ringing. I've been building TLs for years, and they are very satisfying subwoofers.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

yeah, the red lines r more of a measuring thing that i forgot to erase, but yeah im going to put an audioque HD3 15 in it, its tuned at 30 hz according to win isd

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Oh Man Theres Troy

i was attempting a TL box btw, as it seems you knew but i was wondering why house TL boxes are different. i was reading somewhere that house TL boxes r designed not to have any paralell lines for SQ but i dont know how they tune those

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Oh Man Theres Troy

doesnt bose use this in their acoustimass woofers?

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t-roy81 wrote:

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i was attempting a TL box btw, as it seems you knew but i was wondering why house TL boxes are different. i was reading somewhere that house TL boxes r designed not to have any paralell lines for SQ but i dont know how they tune those

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A TL is a TL is a TL. There are different states of mind in the construction of them, but they all do basically the same thing. Parallel walls simply allow the HIGHEST frequencies to potentially start a resonance ACROSS the line, but not along the length of the line. As long as your crossover point is 1) low enough, or b) steep enough, then parallel or tapered walls will make no difference except in the construction complexity. I might also add that a tapered line requires mich more math to build effectively. I mean the overall TUNING numbers all work out the same, length, (average) cross-sectional area, terminus... but if you attempt a tapered line the line must taper correctly or bad things can happen to your response. Honking is the one thing I noticed - attributable to a resonant chamber - similar to the resonant cavity in your car's intake.

There are about 4 or 5 major differnt types of TLs that I can come up with off the top of my head... They all sound really good, but I will warn you right now, TLs are NOT the type of enclosure you are needing if SPL is even a MINOR design requirement. Accuracy is the priority in TL design.

coppellstereo wrote:

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doesnt bose use this in their acoustimass woofers?

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No, the Acoustimass systems are buried woofers. They are basically a woofer between two different lengths of pipe, allowing for two different resonant frequencies. These frequencies are close to one another (about one octave), so as not to cause a huge hole in the response of the overall system. (But we all know that the Acoustimass sounds like crap, right people?)

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

im not sure if were talking about the same thing, this is the type of TL i was talking about


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Oh Man Theres Troy

Yeah, that's pretty close, but the tapers are all over the place in that picture. Wide to narrow to HUGE, to medium... BAD taper. Very bad taper.

That thing would sound like a fart can exhaust.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

haha yeah obviously that was a a quick drawing :-p

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Oh Man Theres Troy