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

DaveCan said:
dfr65a.jpg


http://www.decware.com/newsite/DFR6.htm

Steve has added his modded fe166e to the site for sale. I'd love to do his Corner Horns but don't have the room.. I'm thinking these would be great in a BIB.....
Dave:)

Decware DFR-65
Fs = 50
Vas = 1.593 (45.11 L)
Qts = 0.21

Will anyone confirm my calculations:

Line length: 134.65"
Z Driver: 29.22"
A=B=C: 6.41"

Internal box height: 67.32"
Internal box width: 9.07"
Internal box depth: 12.82"

Vb: 4.53" ft^3
Sm: 116.2" ft^2
 
They match mine except 'Sm' is in square inches, not feet. ;)

That said, I'd just use the 'stock' BIB's height, which is based on a ~48.78 Hz Fs, reducing Sm, etc., a small amount, though I imagine you'll be driving these with a tube amp, so using the larger value is the better choice IMO. Indeed, if you know the amp's output impedance or DF, then I recommend using the effective Qts to calc 'Sm', etc..
 
Re: Re: Flea watts for Monacor BIB

McFaBs said:
Thanks Scott
So no Set for the moment....Do you have any suggestion for a good and low cost 15 watters?
Any experience with diy passive pre?
Ciao. Fab.

Depends on what you call inexpensive. There are some amazing bargains from China to be had, but the transformers are usually an unknown quantity -some are great, others are rubbish, and you simply don't know until it arrives in the post. The KEL84 kit on this page is a good design, with excellent transformers for the money. http://wduk.worldomain.net/acatalog/AmpKits.html
 
Hi again!

I just finished building a bib for fe126e. I built the inverted version, because my ceiling is 3.7m high. I am very satisfied with the sound, although I'm still testing all the stuffing options and I have yet to cut the k slot.

On the other hand, I was shocked how big it really is. You don't apprisiate the size untill you really see them in the room.

That got me thinking.

Could I straighten the pipe and hang it on the wall (mouth facing up)? That would save me enormous amount of space.

The back side would be flat, and the front would be tilted forward.

A thing that is bugging me is: is my ceiling high enough for that. (3.7m). Since the line length is 97" (2.46m) I would get little more than 1m above the bib to the ceiling.

Is that ok.

And other thing is: since the front would be tilted forward, should I build a baffle so that it's tilted back to normal? Or just leave the driver pointing little down?

Thank you very much

P.S. I will post picture of inverted bibs in a couple of days (when I get my camera back from a friend).
 
Yes of course, no reason why not. They should work fine. 1m clearance sounds OK to me. I've got just about that myself. If you're worried about the angles, you could always just build a rectangular box, with a full-length internal sloping baffle splitting it in two (see attached) and use the front half, while filling the sealed-off back part with cat litter or something similar.

I didn't think they were that big though. Mind, I think cabinets about 70in tall x 12in wide & 20in deep are just about right :devilr: so I obviously have a skewed mind... :xeye:
 

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Here are some pictures of my fe126e iBIB:

An externally hosted image should be here but it was not working when we last tested it.

Shot with DiMAGE Z1 at 2007-07-13

You will notice the hi-end solution for the legs. :) It's only temporary

An externally hosted image should be here but it was not working when we last tested it.

Shot at 2007-07-13

An externally hosted image should be here but it was not working when we last tested it.

Shot with DiMAGE Z1 at 2007-07-13

An externally hosted image should be here but it was not working when we last tested it.

Shot with DiMAGE Z1 at 2007-07-13

My faithful assistant, inspecting the glue line :)

All in all, I am very very satisfied with the result. I will leave it like this for a while, but eventually I plan to build a straight pipe, as mentioned on the previous page, because I think it will look so much better hanging of the wall.

At the moment I am playing with stuffing and lining options, and then I will build proper legs. Oh, I forgot to cut the k-slot. Well maybe tomorrow.

Btw- what does it do? I have no idea really.

Thanks for all your help
 
frugal-phile™
Joined 2001
Paid Member
Originally posted by cheda13 Oh, I forgot to cut the k-slot. Well maybe tomorrow.

Btw- what does it do? I have no idea really.

You will note that the sims for the BIB typically have a lot of ripple. This ripple can be heard (but doesn't bother a lot of people). The idea behind the k-slot is that it will smooth the ripple. We don't yet know how well it accomplishes that.

dave
 
Well, kind of. Nothing big, I just play with some friends - just for fun

And that amp is my frinds bass amplifier - I'm just servicing it at the moment.

Mine is something different
http://chejok.freecoolsite.com/

Sorry for the OT.

On the matter of bib:

Some people have asked me why is driver placed so high - not consistent with the zillaspeak data (19.5" from the sealed end)?

Is it because of the floor loading? Or is it influenced by opinion (with wich I agree) that tweeters should be placed little above listening level?
 
Hey all,

I am about to build a pair of FE166e BIBs. I do have a bit of an issue with corner placement in my room. I can’t help but think that having the speakers out into the room is more interesting for imaging. Placing the speakers flat against the wall or directly into the corners would have a negative effect on the imaging properties of my room.

I was wondering if having a 3-fold BIB (to make it twice as deep and half as tall) would have an adverse effect on the frequency ripples. The 3-folds would mean that the cabinet would be 24 inches deep and approx 8 inches wide and the mouth of the horn would be situated on both sides of the cabinet at the bottom rear (it would kind of look like the Big Fun Horn).

This BIB could be placed right in the corners of the room (and make 100% use of corner loading) and still project far enough in the room to offer good enough imaging (having the drivers away from immediate bounderies).

Please let me know if this has been tried of if you think it could have a desastrous effect on the pipe resonnance.

Thanks.
 

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