need help with T line box

Brian Steele · Postby **Brian Steele** » March 3rd, 2015, 7:13 pm

Brian Steele wrote:No frequency response data (simulated or otherwise)
No impedance data (simulated or otherwise)

Watching those videos for guidance on what results you can get is like trying to shop for the best tires to fit your car with the sellers talking about everything else but what's most important - the rim-size and width of their products.

Unfortunately there is a dearth of really good websites covering DIY designs, but they are out there.

Here's a decent one: http://www.audiocircuit.com/DIY/Dynamic ... an-Weeghel

Notice the shape of the line? It's tapered. Maintaining a constant taper throughout a t-line is actually one of the worst ways to build one, particularly if the aim is a full range design. The end result is likely to be needlessly large with audible response aberrations in the passband.

pugboy · Postby **pugboy** » March 3rd, 2015, 8:09 pm

lol, who has not been here ?
I've built many boxes just for the heck of it, all hit and miss but that is part of the fun.
Back then it was cutting all the ply with a jigsaw, didn't own a table saw.

later on I got some sense and built tried designs.
Still haven't gotten around to learning hornresp but it is in the bucket list.

I built a pair of Lynn Olsen Ariel transmission lines many years ago,
http://www.nutshellhifi.com/Ariel.html

First real speakers I built with the right drivers, crossover etc,
unbelievable sound quality from a pair of 5.5" speakers.
Tight real bass and proper high freq with scanspeak drivers.

Brian Steele wrote:Anything else is just fluff or the "let's just build it and see what happens" approach. That last time I took the latter approach to DIY was oh, about 20 years' ago, LOL.

Brian Steele · Postby **Brian Steele** » March 3rd, 2015, 8:34 pm

pugboy wrote:lol, who has not been here ?

True, but the difference between 20 years ago and now is that the DIYer of today has access to a whole lot of cheap or even free tools that can be used to ensure that he doesn't end up wasting time and effort and $$ in building crap, just because someone else said "it sounded good". As you know, when it comes to speakers, one man's "good" is another man's "crap", LOL.

pugboy · Postby **pugboy** » March 3rd, 2015, 9:00 pm

Yes, back then the only info available was loudspeaker magazine or paper books
I bought a book on how to test t/s with signal generator

meccalli · Postby **meccalli** » March 3rd, 2015, 10:40 pm

I think anyone who's interested in building speaker systems should read the loudspeaker cookbook by vance dickinson. It's a book I still haven't completed in it's entirety, but what i've learned from it is pure audio gold to me.

kavaninho · Postby **kavaninho** » March 4th, 2015, 12:25 am

https://docs.google.com/file/d/0B_l73GV ... edit?pli=1

That's the link to the book. It is more of a beginners course, but has essential fundamentals for designing more complex systems. The book also has some nice history about car audio and home audio.

pugboy · Postby **pugboy** » March 4th, 2015, 7:23 am

Definitely, that was one of the first books I got also.

Has extensive info on sealed and ported boxes with examples of the different alignment models. The Tline stuff is a little lacking and there is no horn stuff either.

Horn technology has evolved much recently than sealed/ported designs which have not changed in 30years.

Beginners should start with ported boxes, I built a box for an MTX Blue thunder 12", postbuild tested/adjusted it and to this day the guy says its the best sounding ported box he ever had.

meccalli wrote:I think anyone who's interested in building speaker systems should read the loudspeaker cookbook by vance dickinson. It's a book I still haven't completed in it's entirety, but what i've learned from it is pure audio gold to me.

Brian Steele · Postby **Brian Steele** » March 4th, 2015, 8:13 am

pugboy wrote:Horn technology has evolved much recently than sealed/ported designs which have not changed in 30years.

Nope. "The physics (and mathematics) of horn operation were developed for many years, reaching considerable sophistication before WWII." - http://en.wikipedia.org/wiki/Horn_loudspeaker. Specific horn types like multiple-entry horns however were developed much more recently. And of course software tools like HornResp enable us to quickly model many basic horn types without having to know all the mathematics behind them.

meccalli · Postby **meccalli** » March 4th, 2015, 12:58 pm

Yep, although some guys like danley really did a number on the quality of information we have now on stuff like th's.

kavaninho · Postby **kavaninho** » March 4th, 2015, 3:53 pm

If you guys have any books,articles or websites about horn theory please share them with me

pugboy · Postby **pugboy** » March 4th, 2015, 7:30 pm

Tru dat, but literature and modelling for the layman was not exactly mainstream at same time.
Mind you klipschorn been around a very long time.

Pablo660 · Postby **Pablo660** » March 17th, 2015, 6:09 pm

Ok after a week or 2 the performance have greatly improved due the woofer breaking
I know I haven't graphed and tested, was not sure bass box 6 could do it.
The woofer,Treo ss is under dual 4 ohms per amp channel under around 500w from a JL G4500.
I plan to build a second and I rushed n not put 45 in existing which I will remedy

I'm thinking for everyday driving to build a 4th order band pass to hold both Treos