BIB question

IG81 · 22nd December 2008, 09:30 PM

Ok, so to me the BIB design seems like a back-loaded, folded horn. The position of the driver (Zdriver parameter) is not at the complete throat of the horn, whose lenght is ½FS. So what does the 0.217 Zdriver ratio relate to?

And is it possible to reverse the design upside down so the mouth of the horn points towards the floor, assuming I would keep it above the floor just enough?

Thanks!

gurley123 · 22nd December 2008, 09:43 PM

I know it's a monster thread, but I believe that they want all BiB questions in the BIB thread.

AFAIK the .217 Ratio is used for proper control of the half-wave resonance. Yes you can flip it (then it's called an I-BIB or inverted BIB.) A lot of people have done this and all the information is in the BIB thread. Basically you make an opening in the bottom rear equal to the original mouth area. Some have gone with a diagonal opening also. When doing an IBIB, you can use a ratio of .416(Line) to keep the driver near ear level. This is mostly done with the higher tuned ones (100~70HZ or so.)

Check the main thread for the full story.

IG81 · 23rd December 2008, 02:59 PM

I was not aware of a main BIB thread at the moment I posted that, but I stumbled upon it afterwards. Thanks for the info, I'll gladly check it out!

gurley123 · 23rd December 2008, 03:44 PM

It may take awhile, it's a monster thread but it's full of good information.

Scottmoose · 23rd December 2008, 03:46 PM

Briefly, yes, the BIB is a BLH -a tapped, chamberless, conical corner-horn to be exact. Tap length (Zdriver) is taken to minimise harmonic ripple as far as practicable. Inverting is no problem, plenty have been made like that.

Cal Weldon · 23rd December 2008, 04:22 PM

Quote:

Originally posted by gurley123
it's a monster thread

Be careful

http://www.diyaudio.com/forums/showt...13#post1674813

gurley123 · 23rd December 2008, 04:31 PM

Wow, I had no idea. That's monstrous :P

Anyone want to buy some used cable? I make most of my own these days.

I need to get cracking on some BIBs myself.

22nd December 2008, 09:30 PM	#1
IG81 diyAudio Member Join Date: Feb 2008	BIB question Ok, so to me the BIB design seems like a back-loaded, folded horn. The position of the driver (Zdriver parameter) is not at the complete throat of the horn, whose lenght is ½FS. So what does the 0.217 Zdriver ratio relate to? And is it possible to reverse the design upside down so the mouth of the horn points towards the floor, assuming I would keep it above the floor just enough? Thanks!

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
newbie with input tran. question and wiring question	imo	Solid State	0	18th January 2006 10:10 PM
Capacitor Question /question on cap	TunaFish	Tubes / Valves	14	12th January 2004 02:23 AM
PS question - tformer question actually	breguetphile	Chip Amps	2	30th May 2003 01:29 PM
old speaker question, bullet midrange question & link to speaker project	wallijonn	Multi-Way	10	5th November 2002 06:03 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

22nd December 2008, 09:43 PM	#2
gurley123 diyAudio Member Join Date: Oct 2007	I know it's a monster thread, but I believe that they want all BiB questions in the BIB thread. AFAIK the .217 Ratio is used for proper control of the half-wave resonance. Yes you can flip it (then it's called an I-BIB or inverted BIB.) A lot of people have done this and all the information is in the BIB thread. Basically you make an opening in the bottom rear equal to the original mouth area. Some have gone with a diagonal opening also. When doing an IBIB, you can use a ratio of .416(Line) to keep the driver near ear level. This is mostly done with the higher tuned ones (100~70HZ or so.) Check the main thread for the full story.

23rd December 2008, 02:59 PM	#3
IG81 diyAudio Member Join Date: Feb 2008	I was not aware of a main BIB thread at the moment I posted that, but I stumbled upon it afterwards. Thanks for the info, I'll gladly check it out!

23rd December 2008, 03:44 PM	#4
gurley123 diyAudio Member Join Date: Oct 2007	It may take awhile, it's a monster thread but it's full of good information.

23rd December 2008, 03:46 PM	#5
Scottmoose diyAudio Member Join Date: Mar 2005 Location: UK	Briefly, yes, the BIB is a BLH -a tapped, chamberless, conical corner-horn to be exact. Tap length (Zdriver) is taken to minimise harmonic ripple as far as practicable. Inverting is no problem, plenty have been made like that.

23rd December 2008, 04:31 PM	#7
gurley123 diyAudio Member Join Date: Oct 2007	Wow, I had no idea. That's monstrous :P Anyone want to buy some used cable? I make most of my own these days. I need to get cracking on some BIBs myself.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)