Transmission line enclosure for DD 6,5" test and results

[Haakon]

Just thought I'd share this little project I'm running at the moment. 

A few years back I made a very basic T-line enclosure from a small Focal 5" woofer I had laying around. I used to have four of them in a sealed box, but I popped one, and sold two. So I had one left. Much to my surprise the single woofer in a T-line outperformed all of the four I had earlier, both in depth, loudness and impact. Sounded really nice too! But a single 5" is still a single 5"...

Move on a few years, I thought I'd experiment a bit more but with a more capable driver, yet smaller than just about anyone is using. I bought a new DD 506 (redline) woofer, and relying on the supplied parameters; i made a tapered T-line box for it, using this very simple calculator found here: http://www.mh-audio.nl/tml.asp

You just input the SD and FS on the driver, and the height of the box, and it does the rest. Very basic, but useful as a starting point. I built the quarterwave one (classic tuning). 

Internals of enclosure, 22mm MDF:

 

The subwoofer driver:

Box in car:

This was done just a day after I built it, so possibly more to come later on. Not a burp either, just playing some random music with added bass. I think this was a Pink Floyd song with a pretty strong 44hz bass note added

I do have lots of power on tap, way more than the woofer can handle mechanically in this box (can get it to bottom out pretty easily), running a Helix SPXL1000 at 2ohms (about 1200w rms)

But very impressed with this little woofer in this box ?

 

Thanks for looking! 

[Ron36]

That’s a great little sub and impressive numbers for one 6.5.

[Haakon]

 

[UWDuus]

Hi..

Nice work,

where did you get the Sd value, it isnt listed anywhere in DD audio's Homepage?

I want to try out the Tline design my self, but im not familier to find the sd value my self