Obviously unfinished! The right side is clamped in place. That's one of my old Paradigms doing double duty as a stand to raise the FR125 to ear level, and as the bottom of the cabinet (with a folded dish towel as padding and gasket).
I wound up using plain #2 pine instead of the laminated panels, mostly for cost, but also because it minimized the number of rips needed and I could get two pieces the right length from each 10' board. Hardly any waste!
I wound up using plain #2 pine instead of the laminated panels, mostly for cost, but also because it minimized the number of rips needed and I could get two pieces the right length from each 10' board. Hardly any waste!
Attachments
Ok, so how does the BIB sound?
Be sure to put BIB pix on the BIB site!
I'm gettng close (sort of) to doing a clamp-up
myself. Got the glueup boards at 72 in and have
to get the framing pieces.
Question is: since I want to put some RS 1197's
in these and not do much cutting, the FE103
dimensions show a considerably shorter line
length. I want to get that terminus as close to
the ceiling as I can.
The raw lengths would make long and slender
cabinets but sounding... how? I dunno.
Be sure to put BIB pix on the BIB site!
I'm gettng close (sort of) to doing a clamp-up
myself. Got the glueup boards at 72 in and have
to get the framing pieces.
Question is: since I want to put some RS 1197's
in these and not do much cutting, the FE103
dimensions show a considerably shorter line
length. I want to get that terminus as close to
the ceiling as I can.
The raw lengths would make long and slender
cabinets but sounding... how? I dunno.
How's it sound, you ask?
A little background first: I'm in an 11' W x 14' L x 8' H den with no acoustic treatments at all. The amp was built for me by a friend who worked at Threshold many years ago. It's based on their Forte' 4, with a few changes (extra pair of IGBT output devices). Roughly 50 WPC, high-bias AB operation. Preamp is Joe Curcio's Daniel 2 design, built by yours truly. Sources, a venerable JVC 1050TN CD player, and a much-modified AR-XB turntable with Grace 707 Mk II arm and Shure V15VMR.
Enough already, the sound?
Very nice indeed! Coherent, non-edgy, a little soft on top. A bit colored through the mids, kind of a cupped-hands sound on male voice. Cabinet resonances are probably at play there, this is not a 'dead' box at all, but as the pic's show one side is not yet glued down. Bass is solid to 40, audible even lower, and seems to be going deeper as the driver runs in. This room has a strong resonance around 40 Hz, and it's in fully audible, no 'dipole-like' effect AFAICT. At comfortable listening levels, even fairly strong bass (e.g. Dub Side of the Moon, the Flecktone's "Flight of the Cosmic Hippo") doesn't seem to faze it.
So far, clamped panels flapping in the breeze and all, I'd call it a success. More to come as I finish up the pair.
Bill
A little background first: I'm in an 11' W x 14' L x 8' H den with no acoustic treatments at all. The amp was built for me by a friend who worked at Threshold many years ago. It's based on their Forte' 4, with a few changes (extra pair of IGBT output devices). Roughly 50 WPC, high-bias AB operation. Preamp is Joe Curcio's Daniel 2 design, built by yours truly. Sources, a venerable JVC 1050TN CD player, and a much-modified AR-XB turntable with Grace 707 Mk II arm and Shure V15VMR.
Enough already, the sound?
Very nice indeed! Coherent, non-edgy, a little soft on top. A bit colored through the mids, kind of a cupped-hands sound on male voice. Cabinet resonances are probably at play there, this is not a 'dead' box at all, but as the pic's show one side is not yet glued down. Bass is solid to 40, audible even lower, and seems to be going deeper as the driver runs in. This room has a strong resonance around 40 Hz, and it's in fully audible, no 'dipole-like' effect AFAICT. At comfortable listening levels, even fairly strong bass (e.g. Dub Side of the Moon, the Flecktone's "Flight of the Cosmic Hippo") doesn't seem to faze it.
So far, clamped panels flapping in the breeze and all, I'd call it a success. More to come as I finish up the pair.
Bill
Lousymusician,
Nice pine you have there. How thick are panels and I suppose you have not started playing with damping yet?
In my experience with pine is that you get the same result with chipboard. Of course pine is better due to one can get nice edges almost for free.
I got a huge difference moving my BIBs from a hard ceiling to an acoustical treated ceiling (meaning normal office plates in ceiling).
It will be interesting what stuffing you will end up with.
Best regards Peter
Nice pine you have there. How thick are panels and I suppose you have not started playing with damping yet?
In my experience with pine is that you get the same result with chipboard. Of course pine is better due to one can get nice edges almost for free.
I got a huge difference moving my BIBs from a hard ceiling to an acoustical treated ceiling (meaning normal office plates in ceiling).
It will be interesting what stuffing you will end up with.
Best regards Peter
http://www.zillaspeak.com/bib-pics.asp
http://www.zillaspeak.com/bib-gm.asp
Jordans will be posted later this week. Thanks Scott!
http://www.zillaspeak.com/bib-gm.asp
Jordans will be posted later this week. Thanks Scott!
Scott... can you explain a little more about the Jordan config you sent me please?
'Jordan JXR6 Linear Array BIB'
It's not clear how many drivers are used (2?), impedance considerations.. etc.... it appears to be a very efficient system... tho it may require powerfull SS to drive.
Thanks,
Godzilla
'Jordan JXR6 Linear Array BIB'
It's not clear how many drivers are used (2?), impedance considerations.. etc.... it appears to be a very efficient system... tho it may require powerfull SS to drive.
Thanks,
Godzilla
4 JXR6 drivers per enclosure in a mini array as per the suggestion on the Jordan website. Personally, I remain unconvinced about even short arrays with fullrange units, but if Ted says its OK, then that's good enough for me. I'd still make pretty sure I was listening in the farfield, not the nearfield though, or the polar response will be rough. Hang fire on that one if you can Jeff, I want to check few more things out before signing it off so to speak. The JX92S OTOH should be lovely. No worries there at all. I want one (well, two, but you get the idea... ;-)
housekeeping
I just thought of something about the BIB's.
After time won't a lot of, you know, dust and whatnot
settle from the open terminus? Wait, never mind, the
driver is in a sealed space.
Boy, that was a close one. ;-)
Will the BIB site give actual cabinet dimensions or
is this a freeform dealers choice? I have not done
much with calculation.
I just thought of something about the BIB's.
After time won't a lot of, you know, dust and whatnot
settle from the open terminus? Wait, never mind, the
driver is in a sealed space.
Boy, that was a close one. ;-)
Will the BIB site give actual cabinet dimensions or
is this a freeform dealers choice? I have not done
much with calculation.
peterbrorsson said:
Panels are 3/4 thick. I stole some poly batting from my wife's sewing stash. I cut a strip the width of the enclosure, and ran it from the point above the driver, down the internal panel with a strip of 2" double stick tape to keep it in place. It ends maybe 8" below the driver for now. I'll lay some more of the same in the bottom, once there is an actual bottom. I figure the driver will need some playing time before final tweaking.
I didn't mention last night that with the single thickness baffle the FR125 magnet hits the internal baffle. I had to route out a recess for it, stepped from 1/4" to 1/2" deep.
Attachments
Did you notice any improvement in the mid-range with the poly batting? If that was what you were after with that. My experience with batting was not very good. I found that it absorbed some of the low freqs and let the upper freqs through. In fact if you take a piece of it and hold in to the front of the driver you'll see what I mean. Acousta-stuf I found works better in this regard.
UV
UV
http://www.zillaspeak.com/bib-jordan.asp
I'm drunk... business meeting over... Madeleine Peyroux is singing to me now...
I'm drunk... business meeting over... Madeleine Peyroux is singing to me now...
lousymusician said:
One of the reasons I used to post specific WxD dimensions to ensure that sort of thing didn't happen. And if it did, you had someone else's face to put on the voodoo doll you stick pins in.
Take heed of this warning prospective BIB builders: just make sure what dims you choose allow the driver to fit! Saves so much grief...
Bet they'll still sound good though when they're finished!
seanzozo said:
Greets!
Yes and no since the ceiling extends the virtual horn, lowering Fc and generally smoothing its entire response.
Yes, there are ways to adapt the BIB or short lines (I listed one way many posts ago) to tall ceilings, but these fall into another category and right now we're still trying to do just basic BIBs, or at least I am.
Of course folks are encouraged to come up with their own hybrids and share them with us even if they don't perform well.
GM
Hey lousymusician, how are those FR125's breaking in?
I have a set just sitting on a shelf, that I might see my way clear to boxing up... that design looks interesting!
I think I have sorted out the sizing, having scrubbed this entire thread, but could you clarify that for me?
Total H
Total D
Total W
etc
Thanks!
Almost tempted to try my b200's in one of these... but I really like them in OB, warts and all!
I have a set just sitting on a shelf, that I might see my way clear to boxing up... that design looks interesting!
I think I have sorted out the sizing, having scrubbed this entire thread, but could you clarify that for me?
Total H
Total D
Total W
etc
Thanks!
Almost tempted to try my b200's in one of these... but I really like them in OB, warts and all!
mcgsxr said:
This is lousyspeakerbuilder ;-)
I had the same problem of figuring out dimensioning but
I had an idea. Maybe someone can program a mini-
calculator to put in the height for instance and spit out
the length and depth.
It's just a guess, but I think Greg and the others want us
to calculate the dims from the area of the terminus (horn mouth)
and length of the fold.
I tried to frame this question earlier but no response at that
time. At this time, I have some edge glued shelving that is
72" x 12" scant. The framing would be 3/4 x 6"x6' poplar
or aspen from the HD glued to the inside dimension of the
edge glued stuff. So 12" scant minus 1.5 in front and back and
3/4 minus for the bottom. The trim of the fold would be cut
(the only cut!) to fit the bottom.
Driver selection from my stock would be FE127e, RS1197
(dims from FE103 are closest I suppose) or way down the
food chain, some 50 cent Pioneer 4 inchers from a line array.
I am working up the nerve to let the crew at HD or someplace
do the panel cuts on some better birch plywood. But I worry
that nothing would come out to a fit.
hey lolina,
i'm certainly not one of the experts here but there appears to be very little to calculate. the height is just half the line length of the driver you choose -- 85" (42.5") for the fe103 or 97" (48.5") for the fe126e.
in the fe103 the driver gets mounted 25.5" from the bottom of the speaker (42.5 - 17).
what you have to decide is which combo of width and depth are acceptable to you (and can fit your driver). just make sure the product of the 2 is equal to the Sm.
for example, the fe103 (the dims for less bass) could be 5" x 6.6", or 4.5" x 7.3", etc. for more bass you could use 7" x 7", or 5" x 10", or 6" x 8", etc. just make sure the driver fits. depending on the size of the driver magnet you may need to use a combo of less width and more depth to make sure the piece in the middle allows it to be mounted.
well, this is my understanding at least. i hope others will chime in if i am wrong.
good luck and let us know how it turns out!
i'm certainly not one of the experts here but there appears to be very little to calculate. the height is just half the line length of the driver you choose -- 85" (42.5") for the fe103 or 97" (48.5") for the fe126e.
in the fe103 the driver gets mounted 25.5" from the bottom of the speaker (42.5 - 17).
what you have to decide is which combo of width and depth are acceptable to you (and can fit your driver). just make sure the product of the 2 is equal to the Sm.
for example, the fe103 (the dims for less bass) could be 5" x 6.6", or 4.5" x 7.3", etc. for more bass you could use 7" x 7", or 5" x 10", or 6" x 8", etc. just make sure the driver fits. depending on the size of the driver magnet you may need to use a combo of less width and more depth to make sure the piece in the middle allows it to be mounted.
well, this is my understanding at least. i hope others will chime in if i am wrong.
good luck and let us know how it turns out!