Dave mentioned to me that they were doing OK with the Sigmas, which is good to know.
Nice work on the Pioneer BIB's I was going to try those last year but other things got in the way! I have since downsized just about everything so with that in mind could a BIB be made with a FE 103, how would it sound compared to a Zigmahornet cab. How big would they be? I'm a real newbie here so be gentle with the jargun ( big fancy words) I have to replace a broken pair of speakers, whatever I build will be driven with a near mint NAD 3020e. I started out reading this thread last year, can't believe the # of post's, amazing !
Mark
Mark
Hi Mark!
http://www.zillaspeak.com/bib-pics.asp
The BIBs that are inverted are the ones with the angled bottoms like TCs BIB at the top of the page. Bruces BIB is not inverted. I believe they both use 4 inch Fostex drivers.
http://www.zillaspeak.com/bib-fostex.asp
Here are the original dimensions for several Fostex BIBs. Scroll down and look for the 103/107. I would build the larger cabinet personally, but it depends on the size you desire. Also, many of the suggested dimensions have changed over the past few months so you might want to check out this link below or wait until someone models the 103 BIB again. Should be a great sounding speaker if you use the dims on the page or newer more optimized dims. Im curious to see how different they will be.
http://www.zillaspeak.com/bib-howtobuild.asp
Godzilla
http://www.zillaspeak.com/bib-pics.asp
The BIBs that are inverted are the ones with the angled bottoms like TCs BIB at the top of the page. Bruces BIB is not inverted. I believe they both use 4 inch Fostex drivers.
http://www.zillaspeak.com/bib-fostex.asp
Here are the original dimensions for several Fostex BIBs. Scroll down and look for the 103/107. I would build the larger cabinet personally, but it depends on the size you desire. Also, many of the suggested dimensions have changed over the past few months so you might want to check out this link below or wait until someone models the 103 BIB again. Should be a great sounding speaker if you use the dims on the page or newer more optimized dims. Im curious to see how different they will be.
http://www.zillaspeak.com/bib-howtobuild.asp
Godzilla
loninappleton said:
Hello
I apologize for the late answer, I was out of town.
Damping: not yet. I will wait until the drivers have some 100-150 hours running time, and then I will start putting some damping material following the pattern suggested on Martin J. King's BIB website
Source: LM3886 Gainclone ( Chipamp's kit)
Yamaha CDX-880 CD player
Scottmoose said:
Materials: Mahogany veneered particle board (no veneered MDF here), Poyurethane varnish on sides and back, black poliurethane paint on the front.
regards
Scottmoose said:
1) I believe it has also been accepted that the tuning frequency can be set a little lower than Fs (up to about 30% lower?)
2) Does anyone know the source of the recommended volume formulae: Vb=(20Vas)*(Qt^1.25)
Would this be a general recommendation for pipes, TL etc. ?
SveinB
It's for this particular type of pipe-horn; it's a T/S based alignment created by GM.
Speaking of which, I've just finished a BIB Excel sheet that calculates all the dimensions required. I'm sending Jeff & GM a copy before posting it in case I've made a mistake somewhere (not impossible by any stretch of the imagination -as I said elsewhere, Scott's are designed for many things, but driving Excel is not one of them). But I imagine once checked, it'll be found lurking on the Zillaspeak site.
Speaking of which, I've just finished a BIB Excel sheet that calculates all the dimensions required. I'm sending Jeff & GM a copy before posting it in case I've made a mistake somewhere (not impossible by any stretch of the imagination -as I said elsewhere, Scott's are designed for many things, but driving Excel is not one of them). But I imagine once checked, it'll be found lurking on the Zillaspeak site.
I have plugged all of the dims and the new formulas into the old spreadsheet, and for the FE166E, I'm getting a *huge* difference in CSA... and a huge footprint too...
Line Length 134.65
Zdriver 29.22
Vb (liters) 128.26
Sm – Terminus Area (sq. in.) 3291.99 !!!
Depth 68.23 in.
Width 48.25 in.
Perhaps the problem is that the formulas tune the BIB to an octave lower than Fres, and being the FE166 Fres=50 Hz, this comes out as a 25 Hz tuning freq. There is no way the BIB not be huge...
Am I goofing anywhere ????
Gastón
Line Length 134.65
Zdriver 29.22
Vb (liters) 128.26
Sm – Terminus Area (sq. in.) 3291.99 !!!
Depth 68.23 in.
Width 48.25 in.
Perhaps the problem is that the formulas tune the BIB to an octave lower than Fres, and being the FE166 Fres=50 Hz, this comes out as a 25 Hz tuning freq. There is no way the BIB not be huge...
Am I goofing anywhere ????
Gastón
I understand that the general idea is Bigger is Better, but it might be wortwhile to run a sim to see if doubling of the footprint resulting from the T/S based formula is justified.
Regarding the aspect ratio of the mouth, the ratio of 1.4142 might be a nice proportion, but for smaller size BIB's it might not leave enough room behind the driver.
SveinB.
Regarding the aspect ratio of the mouth, the ratio of 1.4142 might be a nice proportion, but for smaller size BIB's it might not leave enough room behind the driver.
SveinB.
There you go: classic example. No sooner I post the sheet than I find a typo in the Imperial line length calculation. It's now corrected and the sheet uploaded above is the correct one.
I didn't post the pretty one because the pictures I added made it too large. Oh well.
Re the 1.4141 ratio, you either add a baffle or go to something else. That's up to the builder & why an SL area is attached.
Yep, the Vb is justified from the sonics. Better dynamics, freer, more relaxed sound. If you're going to make a pipe-horn, you might as well optimise it. Trust Greg. He knows what he's doing.
I didn't post the pretty one because the pictures I added made it too large. Oh well.
Re the 1.4141 ratio, you either add a baffle or go to something else. That's up to the builder & why an SL area is attached.
Yep, the Vb is justified from the sonics. Better dynamics, freer, more relaxed sound. If you're going to make a pipe-horn, you might as well optimise it. Trust Greg. He knows what he's doing.
ghpicard said:
I do not think we shall consider the 1.4 a sacred number. Terry's original started out with around 2:1 (or even larger). A guy called Bruce Edgar was at some time recommending 2:1 as optimum aspect ratio (for midrange horns), and has later found that 1.6 is even better.
Point is - there is some margin of error here which allows for individual adjustments.
Svein B.