The Metronome

[Tweeker]

Ive been pondering a BiB variant. Something along these lines, ~80" tall:

The Bibazoid.

[Scottmoose]

Could be very interesting. Greg? Dave? What sort of expansion rate / shape would we be looking at here? The standard BIB is basically conical, so I'd guess this would shift it toward being something on the lines of a hyperbolic? My only slight concern would be the transition from the front taper to the rear one might be a bit abrupt. I'm rotten at maths I'm afraid (i.e I'm thick) so I'm going to struggle figuring the dimensions to plug into the latest MathCad BLH Sections sheet as-is.

[planet10]

.

[Tweeker]

Hmmm, thinking about it some more Id probably change the depth from about 16" to 12". It may not be that different from regular BiB, but it eliminates parallel walls. If theres a transition discontinuity, the fold plane could bottom closer to the back wall to adjust such that mouth area is the same at each side.

[Scottmoose]

True. Worth exploring anyway.

[Steve Cresswell]

Scott emailed the response curves and suggested mass loading the cabinets by means of base plate and a 2 inch port fed by a 3 inch long tube.

No hacking of the cabinets was needed. The mass loading ports fire downwards at the floor from behind the base arches and are invisible.

After much testing this afternoon culminating in me removing all the stuffing from the lines, They sound great.
They are even from top to bottom in room and with the help of the sub form a system that works beautifully together.
Coloration is low.
The lines are lined with carpet underlay so the additional stuffing was excessive and robbed the sound of life and dynamics .

I think we have a winner here guys.

I can only imagine what a taller line with a 6 or 8 inch FR driver would sound like, but that's for someone else to try.

Steve

[planet10]

Originally posted by Steve Cresswell
I think we have a winner here guys.

:^)

attached are plans... i had to shrink them a bit to get small enuff to attach so not as clear as i like. (i'll work up a better one for you to post Steve -- i'll also link to whereever you put it from my box-plan page -- i'll also generate the appropriate modeled responses.

dave

[Steve Cresswell]

Hi Dave

Thanks - that's fantastic.

Best Wishes and I hope they can be developed into a range of enclosures for larger drivers.

If anyone builds these with the FE108 Sigma they need to be aware that a good quality active subwoofer is absolutely essential for best results.

Steve

[Scottmoose]

I'm working on one for the FE167E at the moment. Plus, there's a bipole variation in the wings using 2 FE126Es.

[planet10]

Originally posted by Scottmoose
Plus, there's a bipole variation in the wings using 2 FE126Es.

I haven't done the plans yet so Chris doesn't know it is on the build list, but 20 more FE126e arrive tomorrow

dave