transmission line enclosure

So I've been reading up on different style boxes, how and why they work, and I'm a little confused with this type of enclosure... I noticed that design is similar to how bose makes their wave radio (i think)... anyways, my question is, with all of the turns on the inside of the box, do those turns act like a port in any way? My 1st guess would be yes, but I have been wrong before... Thanks for the info......don't crush the weasel...

Well, yes and no... First of all, NEVER mention Bose in this forum again, unless you are considering trading up! (Cause that's all you CAN do for it!) Bose does use TL designs, but the marketing geniuses over there thought that "Acoustimass" and (most recently) "Proprietary Waveguide Speaker Technology" sounded better! Nice, huh? Hell, I'd buy something called "Proprietary Waveguide Speaker Technology", if I didn't know better!! Sounds so... technical, and... scientific, doesn't it? LOL And now you know why 80% of their annual operating costs go directly to advertising, rather than R&D. A port is just a device to tune an enclosure to a given resonance. Remove the enclosure, and buld the port SO big, that you can stick the woofer on the end of it, and there you are - a TL. Oversimplified, certainly, but basically... Instead of an air pump moving air through it, it's a speaker moving air through it. OK, seriously though, the TL is more about organ pipes. It is designed with a single resonance in mind, like an organ pipe, and that resonance is VERY low, compared to a vented enclosure. Above the resonance nearly all of the sound being produced comes from the driver, as the frequency being produced gets lower, the pipe then begins to produce output, until the sound being produced is shared by the woofer and the terminus, but 90 degrees apart. 90 degrees, so it is additive, thus great authority "down low", much lower than an equivalently sized sealed or vented enclosure. Just like a vented enclosure, though, a TL will unload below resonance, just as does a vented enclosure, so a subsonic filter is still necessary.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."

If you need help, PLEASE ask! I've built many TL's in my day, from 300 pound refrigerator size monsters with Radio Shack 18's, to the single 10" iso-loaded stuffed TL in my trunk right now! I love building them!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."

Good call on the Bose. It's hard to believe people buy their crap! "If you bought Bose, You got Hosed". It's sad to see to highend cars with such bad sounding systems and the manufactures going out of their way to advertise the fact. Bryston, (highend home, pro stuff) distributes a company called PMC (Professional Monitor Corp) that is big into the TL style boxes. Pretty cool stuff. Might be some interesting info. If I could get a third mortgage, they would be in the living room.

I prefer this one: "No highs, no lows? Must be Bose" LOL! Love Bryston. Did you know they make fantastic plate amps now, too?

haemphyst wrote: Just like a vented enclosure, though, a TL will unload below resonance, just as does a vented enclosure, so a subsonic filter is still necessary.

Wow... did I actually WRITE that? Talk about the Department of Redundancy Department...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."

The Bryston stuff has always been incredible, The 20 year warranty is reason enough. The other cool amp they have is the 2B-LP. Who else is doing TL stuff?

Sorry... my mailbox was full... got some space now! Now, what are you asking about? I'm lost. (And I'm truly not trying to be obnoxious about that, either... I really am lost!) The TL is certainly NOT where you want to go for mid-bass - it's completely impractical there, due to their physical size. Are you asking about the whole system, and what I'd do, or are you asking about TL design? TLs are also notoriously INefficient. VERY good extension, and generally meant to be a true subwoofer system, you'd rarely, if EVER cross them over higher than about 60Hz, which is where I am with mine right now. Output monsters, they ain't, though.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."

You did say MA Audio right . . . "First of all, NEVER mention Bose in this forum again, unless you are considering trading up!" In this case Bose would be a trade up. (I also have some MA 6.5 component speakers that I could use in the enclosure) you do understand the front stage/rear fill idea? Sealing off the back of the drivers will reduce your mid/bass if they are IB drivers.