Terry Cain's BIB -why does it work and does anyone have those Fostex Craft Handbooks?

[airframe]

Just looked at Godzillas site on BIB nice work Scott and thanks for hosting Jeff, all should visit!!

http://www.zillaspeak.com/bib.asp

Jeff and others, TB 3" er's requires floor loading, so how do you figure out the angle or how high to come up the back??
What is the black peice in the middle at the back?? Support odviously, but would its constuction / position affect anything??

Tangband W3-871S 3" full range - Designed by GM
L = (Line length) 70"
Zdriver = Driver 15.2" down from sealed end of cabinet
Sm = 22.5"^2

SM is W X D does that mean any nunbers that fit the 22.5 cubic inches if I'm reading / undestanding this right will work, like really wide but not deep or just wide enough for the driver and very deep!!!

[Andrewbee]

Hi GM,

I assume this is the FW208N

Yes, correct assumption.

I am just thinking aloud so to speak. I also feel the floor loading would do well, pehaps cutting the mouth at an angle to increase the area.

I wonder if anyone has tried the floor load yet? No reson why it would not work.

I was thinking of a BIB with a woofer mounted as usual and the front baffle being somewhat like the Herb Jeschke (sp) pipe with the FR mounted in "outboard" part of the baffle.

Thanks for confirming my thoughts.

Andrew

[GM]

Originally posted by airframe
Jeff and others, TB 3" er's requires floor loading, so how do you figure out the angle or how high to come up the back??
What is the black peice in the middle at the back?? Support odviously, but would its constuction / position affect anything??

SM is W X D does that mean any nunbers that fit the 22.5 cubic inches if I'm reading / undestanding this right will work, like really wide but not deep or just wide enough for the driver and very deep!!!

Greets!

What angle?

Come up the back?

Black piece?

Anyway, I assume you mean the internal baffle board and its angle, which is defined here: http://www.zillaspeak.com/bib-howtobuild.asp

The WxD dimensions chosen affects the flare rate through the bend, so use this calculator from post 907 to ~accurately maintain a linear one, then you can figure the baffle board location, length: http://www.diyaudio.com/forums/attac...amp=1150943000

GM

[GM]

Originally posted by Andrewbee
..............pehaps cutting the mouth at an angle to increase the area.

Thanks for confirming my thoughts.

Greets!

You're welcome!

Yes, the best way to load it is to seal off the bottom and cut off one corner at a 45 deg angle to create a triangular terminus, then experiment with the distance from the corner's apex and matching distance to the floor.

GM

[Scottmoose]

You know, I never expected this thread to become so long when I started it last year. Nice that people are once again trying this classic style of cabinet and discovering that there is much merit in some of the more traditional ways of doing things.

Some bass horn versions are on the way for the 'Zilla pages. A few Monacors, Seas and Fostex units. They'll be there more as examples than anything else: there are so many drivers we'd be sowed under if we tried doing many.

Just seen Ray's FE168ESigma boxes -lovely.

[zek]

This thread are so long (more than 1015 posts), but there are no one complete BIB project with full explanation of the beginning to final product.
I think there would be several steps:
Step 1: How to select apropriate driver according to it`s T/S parameters
Step 2: How to calculate L - line lenght (depends of Fs)
Step 3: How to calculate Sm - terminus area (depends of T/S parametres)
Step 4: How to calculate So - driver down from closed end
Step 5: How to calculate internal and external dimensions of BIB enclosure (W, D, H)
Step 6: Damping, adjusting and positioning the BIB
Step 7: How it sounds (comparison with known commercial speakers)

If someone want to help, I will make some sketches if needed, and everything can be placed on Zilla`s site `How to build a BIB`
Think about these
Best regards
Zek

[Ray Collins]

Thanks Scott. Where did you see them? They are not up on the BIB site yet.
Also, thanks for the encouragement and guidance when I was contemplating the project. I am very pleased with the results.

Ray

[dmason]

Ray,

[Scottmoose]

Uncle Dan waved his magic wand to both me and Terry Cain, Ray. Hope you don't mind. That's a heck of a finish you've achieved -if I could get mine half as good I'd be a happy man. I'm really glad you like them. Just wait until the usual 100 hour cook time has elapsed.

Best
Scott

PS: The Kingdom of Heaven soundtrack guys -you need to hear this one. If you have one hair on the back of your neck standing after hearing the opening track, check your pulse. Particularly good through 165s.

[Ray Collins]

Scott,
I am flattered that Dan considered it worthy of a pass-on.
Regarding the sound track....consider it purchased.

By the way.....I am in Destin, Fl. with my wife and friends celebrating my birthday weekend......61. OK, OK...I know...but every still works...well!!!!!

Ray