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

GM,

Good Afternoon. You discussed a corner loaded 90 degree wall angle conical horn for the Hemp FR8 in post #194. Two questions. 1. Are the angles in the triangular crossection 60x60x60 or 45x90x45? I know that they are called 90 degree wall angle, but is that referencing the angle of the corner or the cross section?2. Does this design have any negatives? Thanks. I finally received my drivers today. I think espeaker.com sent them by pony express. I will be out of town for the next two weeks, but will start construction as soon as I get back.

James
 
Greets!

Actually, I didn't give it any thought. Use whatever you want as long as the CSA is reasonably close since the angle will only affect how far from the corner the vent needs to be for best performance and you're going to have to experiment to find it anyway.

GM
 
peterbrorsson said:
Hi Scott!
The Monacor SP200MX8 must be a TVM ARZ 6608 which sells for about 9 euro here in Cz Rep.
Check out the Monacor SP155X with a 91.5 db efficiency. Looks like a candidate for BIB.
Regarding the SPH60x being a bit polite in the highs, there is a version SPH68X/AD which sports a rise around 8 k.
Also a whizzer free version added below. Albeit a low efficiency.
All these under 25 euro/pcs
Cheers
http://www.tvm-valmez.cz/index.php?id=110&catit=186&l=1&catg=27
http://www.spectrumaudio.de/breit/m...rumaudio.de/breit/monacor/monacorSPW1168.html

Hi

I never did reply to this did I? I do apologise, the thread's got so large I missed some things. I started to go back over it last night out of interest and finally ran across it.

Many thanks for the links. Yes, those Monacors do look nice don't they. I gather from Dan that they've got a good reputation, especially in Germany. I'm going to take a pair of BIB boxes to EggFest 3 in June with a couple of SPH-60Xs in, just to watch a few faces drop at how much sound you can squeeze out of a 5in driver ;-)

You've helped with something else here though. Remember we mentioned the Polish AcuHorn's; specifically the 125 which is apparantly an inverted BIB? Well, both Dan and I speculated at the time that the driver was likely the Monacor SP-200X 8in unit going by a different name (Tesla), although for the driver Fs, the horn length seemed a bit short. OK, fast forward to last night when I finally ran across your post, and decided to have a gander at those TVM ARZ 6608 drivers you linked to.

Well, they're not Monacor SP-200X drivers (haven't seen the MX8 type, so can't comment there) -the Fs is too high at ~70Hz, and there are other T/S differences too. But they do look very similar indeed, and that reminded me of those AcuHorns. Right size, exactly right appearance -and their Fs is smack on for the line length, which going by the cabinet dimensions on their website, is about 95.5in.

I've run a Google search on Tesla, and effectively found nothing -apart from this at Parts Express of all places: http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=300-007 a 2 way ceiling speaker under the Tesla brand-name. And look where it says it's made.

Coincidence? ;)

MathCad model of AcuHorn enclosure assuming these TVM drivers is below. Given that they are inverted and floor-firing, I suspect bass should be considerably boosted over what is indicated below 80Hz, and the ripple mostly flattened out.

Best
Scott
 

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Hi

I never did reply to this did I? I do apologise, the thread's got so large I missed some things. I started to go back over it last night out of interest and finally ran across it.

Many thanks for the links. Yes, those Monacors do look nice don't they. I gather from Dan that they've got a good reputation, especially in Germany. I'm going to take a pair of BIB boxes to EggFest 3 in June with a couple of SPH-60Xs in, just to watch a few faces drop at how much sound you can squeeze out of a 5in driver ;-)

You've helped with something else here though. Remember we mentioned the Polish AcuHorn's; specifically the 125 which is apparantly an inverted BIB? Well, both Dan and I speculated at the time that the driver was likely the Monacor SP-200X 8in unit going by a different name (Tesla), although for the driver Fs, the horn length seemed a bit short. OK, fast forward to last night when I finally ran across your post, and decided to have a gander at those TVM ARZ 6608 drivers you linked to.

Well, they're not Monacor SP-200X drivers (haven't seen the MX8 type, so can't comment there) -the Fs is too high at ~70Hz, and there are other T/S differences too. But they do look very similar indeed, and that reminded me of those AcuHorns. Right size, exactly right appearance -and their Fs is smack on for the line length, which going by the cabinet dimensions on their website, is about 95.5in.

I've run a Google search on Tesla, and effectively found nothing -apart from this at Parts Express of all places: http://www.partsexpress.com/pe/show...tnumber=300-007 a 2 way ceiling speaker under the Tesla brand-name. And look where it says it's made.

Coincidence?

MathCad model of AcuHorn enclosure assuming these TVM drivers is below. Given that they are inverted and floor-firing, I suspect bass should be considerably boosted over what is indicated below 80Hz, and the ripple mostly flattened out.

Best
Scott




Hi Scott!
Well I finally got my panels cut for my SPH60X and my better half and children going away for two weeks, time for wood working, eh? Hmm, mixed emotions...
However try the their web page below instead of Tesla. It looks like they changed name to TVM. Regarding the Monacors, I suspect the SP200X is a modified version that"Tesla" produce for Monacor. Or worse, Monacor is boosting the specs. Not the first time in history.

Regards Peter







http://www.tvm-valmez.cz






;) :(
 
Could it actually be possible that a $10 Czech made ceiling driver is responsible for the wide acclaim given the Acuhorns from Audio Clubs across Europe?? The models on the Czech site certainly look like the Monacor, with that unique cowling behind the cone. I have a feeling this firm does this line of 200mm drivers for Monacor. ...Doesn't look too advantageous a shape that cowling, however. Something might not be right. Perhaps the Acuhorn company has drivers built to spec. On the other hand, the parameters suggest something that reflects an Acuhorn performance.

An inverted BIB has popped up on the market, the Maxxhorn, www.maxxhorn.com which uses the same basic design, inverted, this would be analogous to upside down BIB, or Acuhorn 125. It uses the PHL 1240 coaxial driver. Our idea excels because without crossovers, there is no need for V-Caps or coils. I am sure the PHL is a tasty choice, very fine transducers. They damn well better be, because the "introductory" pricing is -- get this: $8,600. That's eight thousand six hundred dollars for a suboptimal BIB design with crossovers, sand, copper funnels, circuit suicide, and ....proprietary BassMaxx technology. As if we need that. So, there is another argument in favor of DIY!!

Perhaps we can get some comments about lining the insides. I lined one side of the BIB, and a bit of foam on the interior baffle behind the driver, that is it. What did every/anyone else use? Clark?
 
bassmaxx, well they shure didn't try to spare parts cost. Bybee Large Quantum Purifiers are $75 a hit, if your not talking GOLD;) Looking like a nice collection of expensive parts. How does it sound? Hopefully dam good.

The BassMaxx Technology, though intrests me. If it the same chip that I read about in AudioXpress a while back. It was a chip that blended higher frequencies to produce low ones. Like organists didn't when it was found the the lows were bringing down the church. Literary

But as stated in last post if the BIB is produceing 40hz and below honestly with a 6 to 8" driver. Who needs a chip?:D
 
Maxxhorn states their unit produces 40Hz flat with the BassMaxx chip, or whatever, but the Fostex FE168Sigma easily produces that, and much more than that, in a BIB without ANY circuitry, XO, Bybees, sandstorm resistor, copper funnel clouds, nothing at all. This to me represents a superior design from an implementation standpoint. -- In Classical Science, it is accepted that the simplest solution is generally the best. "The Elegant Solution," in other words. This maxim shows up time and again in ALL the disciplines, and I can think of examples in some of the ones I know, chemistry, toxicology, and pathology, come to mind.. All I know is that after two years of listening to wide band drivers almost exclusively, and having gone thru a blizzard of purchasing and testing, I now find even truly well implemented two way combos sound just plain, well, ...broken, to me. Phase issues and weird timbral dissimilarities in part caused by material and phase dissimilarities are all too apparent now. I am not saying they were "bad," but merely sounded "broken," to me.

The Maxxhorn is basically an upside down BIB, with some great finish work, and some shi shi doodads with a very outstanding PHL coaxial, all for $8,600. I am astounded. I think my BIB looks nicer, more austere, more like fine furniture. For that kind of dough I would own active XO, with RTA, room correction, parametric EQ, DI/O, non oversampling DAC, Olive Musica, and a couple of amps, maybe a GC or T, and 2A3SET, and a powered bass BIB. Geeesh...WTF?? ...Gentlemen, start your saws, says I.
 
I really, really hope AcuHorn have a modified or exclusive range of drivers over the straight, 9Euro ones. Honestly. But I wonder. This would be about the most extreme example I've ever seen in the high end, outside the voodoo drivel surrounding £4500 cables. The driver specs are right though. Please pardon my suspicious nature. As I say, I hope I'm wrong.

Incidentally, (shame faced!) I confess I made a bit of a mistake with the above sim -I forgot that being inverted, the driver will move to a sub-optimal position. The result? Well, in 1/2 space, there'll be a ruddy great 30 db hole with a 10db spike in the middle between 100-200Hz. Being downward firing, I imagine that will be largely flattened out -I hope so, or music is going to sound very strange!

Dan -my saw has already started for the show-pair with Monacors. Out of interest, I think I'll also try for a square cross-section too, rather than the usual. Could be interesting.
I was going to just use some iron-on veneer, but I've got some of this crown-cut weathered sycamore (love that warm pink tinge) in the garage -what do you reckon? Sand it with some 300grit, then a few coats of oil I suspect will allow it to give of its best.

Best
Scott
 

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Fostex FE 103 Sigma

I've been following this thread but could not find the information on the dimensions to make the most for my pair of Fostex FE 103 Sigma.
Of course informations for standard FE 103 is readily available...
This BIB seems quite interesting and easy to make and I'd like to give a try...thx
 
Fostex FE 103 Sigma

That'all the information I could get in german

FOSTEX FE103sigma

Bandbreite 80-20000 Hz
Schalld. 89 dB
Nennimpedanz/Gleichstromwiderstand: 8 / 7,3 Ohm
Resonanzfrequenz: 80 Hz
Gütefaktoren(Qms/Qes/Qts): 2,8 / 0,29 / 0,26
Äquivalenzvolumen(Vas): 6,2 Liter
Effektive Membranfläche(Sd): 55 cm²
Antriebsfaktor(BL): 5,8 Tm
Schwingspulenüberhang(Xmax): 0,35 mm

THX
 
"All I know is that after two years of listening to wide band drivers almost exclusively, and having gone thru a blizzard of purchasing and testing, I now find even truly well implemented two way combos sound just plain, well, ...broken, to me. Phase issues and weird timbral dissimilarities in part caused by material and phase dissimilarities are all too apparent now. I am not saying they were "bad," but merely sounded "broken," to me."

Yes, I agree!

What's neat about the BIB is how it attemts to enhance the bass. (i still havnt heard one yet LOL) but the sims say it will bring up the bass maximizing the 'full range' drivers performance. This way we get to keep our 'full range' sound... no crossovers to muck things up.

Good luck building the monacors... the wood choice looks lovely.

http://www.zillaspeak.com/bib.asp
 
Thanks Jeff, that's what I thought when I first saw it. I'm thinking a couple of coats of Tung Oil and another of lemon oil should do the trick. Any other suggestions guys?

The Fs on the 103Sigma is a bit high. Still, this should work passably:

Try a length line length of 85in, a driver position 17in from the sealed end and a mouth area of 33in^2. Get you to 60Hz or so. Ripple isn't any worse than others, but the short line length might be more of a problem. One option might be to place it on a deep corner-shelf. Ditto for the other sub 5in driver types too. Just a thought.

Best
Scott
 
Greets!

FWIW, the measured specs I have for a pair of FE103S is considerably different:

65 Hz Fs
11 L Vas
3.1 Qms
0.26 Qes
0.23988 Qts
6 ohms Re
38.4 cm^2 Sd

calc'd:

3.2741 N/A BL
92.51 dB/W/m eff.

BTW, the German specs calc a 92.25 dB/W/m eff.

Anyway, unless you have measured specs for your pair, best to use my specs as it makes the pipe a bit larger, which is better than too small a pipe.

GM
 
Scott

I am glad you addressed that for yourself; my immediate thought was, "did you proof read your thesis?"

Good luck with the Monacor 5, again, Louis Chochos of Omega Loudspeakers picked up a pair, and built two BR boxes out of Ebony veneered clinkers he had gathered up. Took the speakers to a Quest For Sound show, and many thought his little creations upstaged the new Zu Tone, which was being unveiled at the show. A little story Zu would rather no one outside of the audience knew about, I am sure. And this from a simple and small BR. BTW, Louis thought the Monacor 5 in a BIB would be "amazing," and conveyed that it would be his own first choice, but cautioned that it needs some juice, at least 10 watts tube, and the small T chips proved lacking. He used a PP 6V6 amp and all were slayed by the combo. They were fun speakers which he actually sold at the show. Keep us informed.
 
GM said:
Greets!

FWIW, the measured specs I have for a pair of FE103S is considerably different:

65 Hz Fs
11 L Vas
3.1 Qms
0.26 Qes
0.23988 Qts
6 ohms Re
38.4 cm^2 Sd

calc'd:

3.2741 N/A BL
92.51 dB/W/m eff.

BTW, the German specs calc a 92.25 dB/W/m eff.

Anyway, unless you have measured specs for your pair, best to use my specs as it makes the pipe a bit larger, which is better than too small a pipe.

GM
Thank you, I'll follow your advice
 
Just read through this long but excellent thread...

The first time I heard BIBs was with RS drivers some years ago, I was surprised by the bass response to say the least. I asked TC once back in the pre-Tiki FR Forum days if the 'tuneful bass' was partlly due to the Ceiling Loaded effect.

http://homepage3.nifty.com/spida/framepage eng-9.htm
(check out the Nagaoka 'Nessie' designs)

Apart from the Supravox 165LB (which was bad at sim), did anyone try to sim the 8" non-whizzered 215RTF64 (not the high Qts sig)? It's not really FR but can be augmented with horn tweets for the highs. Hope it doesn't need to be inverted (extra plaform to support mouth for floor loading)... It's still fairly high Qts, but among the permanent magnet line up it has the lowest Xmax.


BTW, is it okay to use 24mm thick material for all the panels especially for the internal baffle fold? I can only double up 12mm ply, the 18mm that's available here is much lower in quality (lots of voids).


GM,

I learned a lot from our recent email exchange re: altec system. Thanksabunch.:)