Possible wide baffle project

[Scottmoose]

Okay, the room is finally clear after a serious and painful sort-out. Several old prototypes have been binned. My much loved Ariels have been sold on, as have a couple of pairs of MLTLs, whilst the open-baffle project, now complete, has been placed in storage with the Tannoys until I have a larger room. I’m once again building a pair of Martin’s ML TQWT (my third pair –the first two have been swiped by friends), which will be my regular listening speaker. They should be finished and in-place by the end of the weekend.

But now, thanks to my post summer clean-out I have a pair of FE207Es and a couple of spare sheets of MDF lying around. This is an unnatural state, and something must be done. Especially as I like to have a project to work on over the winter. So here’s the idea. I’ve already built a pair of Martin’s MLTLs with the 207, and liked them a lot. And of late, I’ve got interested in the considerable potential wide-baffle speakers offer, so the idea of combining them has some appeal. I’m still at the kicking ideas around stage, but so far, the dimensions mooted are as follows. Line length remains the same (obviously) at 42”. Width triples to 28.5”, and depth reduces to 4”. The front baffle is slightly curved backward to maintain the same So and Sm dimensions. The driver will be mounted on a false-baffle to allow it to fit within the shallower cabinet.

OK, that’s the plan gentlemen (and any ladies out there). Any thoughts or comments on it will be greatly appreciated

Cheers
Scott

[one1speed]

Interesting...one thought comes to mind. Since you like the MLTLs you built, you could simply make only the front board wider/taller and keep the box the same behind the baffle.

One other thought, Tom Z has put a box design together for the FR125 that essentially is a wide horn of sorts. (check out www.fullrangedriver.com) He said he tried many boxes and this design really works. I wonder if it could be adapted for the 207??

Best of luck.

[Dumbass]

Even though the baffle would be wide, the driver would be still very close to top, right? And chance of moving the driver down a bit?

Have you tried any phase-plugging? I recently installed the wrench socket phase plugs on my FE207E, was very pleased with what it's done to the upper mids and highs.

[Scottmoose]

Shifting the driver in an MLTL is a little tricky due to the way the line works. I'll play around in MathCad for a bit and see what gives before starting any work.
I haven't tried any phase-plugs -yet! Actually, I've been meaning to for a while, so this should be the right time to try it out!

Those FR125s sound interesting too -I'll have to think about that...

Cheers for the input
Scott

[Dumbass]

One more thought, with the shallow enclosure you might end up with not enough depth for the port (you want at least 2" between the inside end of port and the back wall IIRC). So consider venting to the side (mirrored pair, natch). Or you could set up a stand like the Jordan VTL and downward vent, or stand with reflector like this:
http://www.quarter-wave.com/Gallery/Jay_ML_TL.jpg

[Dumbass]

Oops, one more idea. Instead of changing the driver position, just have the front baffle extend upward beyond the enclosure. Or just build a taller box and put a partition in there to keep the TL dims the same.

[Scottmoose]

Both good suggestions -many thanks, I'll include them in the design I'm drawing up
Cheers
Scott