Re: Flaws in my Bib?
Hmm, this is about what it should measure out well away from any ~solid boundaries (half space), so in 1/8th space (corner) it should be full down to around 40 Hz with only a 7 ft. ceiling. Combined with a high output impedance amp I'm very surprised you're not complaining of excessive mid-bass bias. Then again, that may be the problem, so give them a try with a SS amp to see if they sound more tonally balanced over a wider BW.
GM
tcrane said:
Hmm, this is about what it should measure out well away from any ~solid boundaries (half space), so in 1/8th space (corner) it should be full down to around 40 Hz with only a 7 ft. ceiling. Combined with a high output impedance amp I'm very surprised you're not complaining of excessive mid-bass bias. Then again, that may be the problem, so give them a try with a SS amp to see if they sound more tonally balanced over a wider BW.
GM
Will repeat my test using a Scott 299 and a Nad receiver to see what happens.
the dimensions for this bib came from an excel spreadsheet downloaded from the depths of this very thread.
the dimensions for this bib came from an excel spreadsheet downloaded from the depths of this very thread.
rjbond3rd
dimensions of bib are:
Driver Brand Fostex
Driver Model FE103E
Fs 79.5
Vas (cu. Ft) 0.24
Qts 0.36
Line Length 84.683
Folded Height 42.341
Vb 1.339
Sm 54.626
Depth (internal) 8.789
Width (internal) 6.215
zdriver 18.376
a-b-c 4.395
My previous post slipped out of fingers before I could add this.
tc
dimensions of bib are:
Driver Brand Fostex
Driver Model FE103E
Fs 79.5
Vas (cu. Ft) 0.24
Qts 0.36
Line Length 84.683
Folded Height 42.341
Vb 1.339
Sm 54.626
Depth (internal) 8.789
Width (internal) 6.215
zdriver 18.376
a-b-c 4.395
My previous post slipped out of fingers before I could add this.
tc
As this is such a popular thread I thought I'd link to one I started about my Neofone Bib. I hope that's not an issue (if it is I'm happy for this post to be deleted) and I really need some help with this.
I'm really, really disappointed they aren't working as I hoped, so before burning them I'm happy to spend time responding to suggestions and tweaking where I can.
Cheers
Brian
Neofone Bib Thread
I'm really, really disappointed they aren't working as I hoped, so before burning them I'm happy to spend time responding to suggestions and tweaking where I can.
Cheers
Brian
Neofone Bib Thread
tcrane said:
So which do you have, a RS 40-1197 'FE103' or a Fostex FE103E? The RS '103' hasn't been one and the same since the '70s AFAIK. For sure they don't have similar specs with the FE103E requiring a longer, larger BIB that will require more damping if a 40-1197 is used.
GM
Brain said:
I prefer that all BIBs be in this thread, so that I only have to search it, but a link is better than nothing.
Anyway, I'm not familiar with the driver, but spec-wise I see nothing other than a potentially too high an output source impedance along with the aforementioned air leak(s) and proper damping behind the driver to cause your problems.
Note too that these pipes acoustically mass loads (damps) the driver's diaphragm much more than a BR, so as others have suggested, a super tweeter may be required to tonally balance it out as well as increase its perceived LF clarity since the lower the frequency, the wider its BW.
GM
Thanks for the reply.
Now that I've made the cabinet, can you suggest a suitable driver to replace the NF?
Cheers again
Now that I've made the cabinet, can you suggest a suitable driver to replace the NF?
Cheers again
GM said:
Sorry but I don't get that at all. I thought you indicated earlier on that the NF may not be suitable for a BIB?? I apologise if I've failed to understand but surely something with similar specs would also sound gash in the same way?
It's taken me a long time to get around to building this BIB for the Neofone, I had believed it was suitable despite not really understanding it much. If I've made a mistake I'd like to put it right. I like the look of the cabinet and my wife is happy with it too, so if it needs another driver to get it sounding good I'll have to work at tracking one down. or of course, build another cabinet for a driver that is known to work.
Cheers again
Hi Brian, in other words, there are other drivers that would use the same line length and cross-sectional area as the cab that you built (roughly).
It's common to try dozens of tweaks etc. and then one of them "locks" it all in. @verk on the other thread said it worked, so keep trying, especially the stuffing angle. Swapping out different drivers is all part of the fun. :0
It's common to try dozens of tweaks etc. and then one of them "locks" it all in. @verk on the other thread said it worked, so keep trying, especially the stuffing angle. Swapping out different drivers is all part of the fun. :0
it looks like the fostex fe168es would do well in your cab, and you may even be able to go with a jordan jx92 or a monacor sp-60x if on a budget.
however, i would definitely play around with damping, room positioning, other amps, etc. before changing drivers. have you tried pulling them away from the walls? not sure if you said it before, but what is your room like?
however, i would definitely play around with damping, room positioning, other amps, etc. before changing drivers. have you tried pulling them away from the walls? not sure if you said it before, but what is your room like?
I have the RS 40-1197, sigh... The dimensions that I posted were copied from a spreadsheet. That would explain a lot if these have different specs. Thanks for bringing this to my attention. Since the cabinets are already built, I guess the thing to do is to get some actual fe103s to try.
Any suggestions as to a good application for the RS 40-1197?
tc
rjbond3rd said:
I'm going to be trying a bit more with the stuffing later this evening and will report back.
giantstairs said:
The room is 22' x 11.5' with no recess type areas or anything of that nature. I placed the speakers about 6" from the side walls and about 4" from the rear and that's where I'd like them to stay, so I want to make the tweaks on the cabinet work for that position if possible. They look quite nice there even though they're just bare MDF. Amazing really. The dimensions just look right, if you know what I mean.
I'll see how it goes with the tweaks and will only look at other drivers as a last resort.
Thanks to you both.
Hello every one 🙂
I have read a large part of this thread (more or less the first half and the last 30 pages, having subscribed to the thread) and I feel ready to attempt my BIB-building for a pair of AN8 standard. I also got some very kind and precious advice from Jeff-Godzilla and I want to thank you all: this reading has been a thrilling experience, leading me to learn a lot on speaker building and hi-fi in general. I wish I had known this forum before building my actual cabinets... (if I think of the time it took me the finishing of those cabinets... I won't build a new couple!).
I still have some doubts and I hope that some one can help me. As I have not read the full thread it is possible that some of this has already been answered - I bag your pardon for this.
1) I found differences between the size of Sm calculated with the BIB calculators (=133"^2) and the measures provided by Godzilla in his site (168"^2). Why does this happen? Is there a reason to use a larger Sm?
2) In the formula to calculate Sm there is a value (1728 imperial, that is 12^3; 61.0237 metric) - where does this come from?
3) Stuffing - maybe this is the real "newbie" question, very naif... but how do I keep in place the stuffing above and around the driver? Won't it fall down? I hope the question is not too silly!
4) Apart from tcrane (post #4294) did anybody measure BIB performance? If so, do measures fit with the model or not? that would one of the most interesting things to know.
5) Suprabaffle question. For various reasons, I think I will do something similar to what Godzilla did: a large wooden rectangular panel, all over the front baffle. What if I mounted it in such a way that the speaker were not centered? Could it be useful?
I will test my cabinets with a Trends TA10.1 + Promitheus TVC passive pre, with a NAD 3220PE and, hopefully soon, with a VirtueAudi😵NE.
A huge thank you, for the pleasure I got reading this thread and for the replies to all my questions.
Guido
I have read a large part of this thread (more or less the first half and the last 30 pages, having subscribed to the thread) and I feel ready to attempt my BIB-building for a pair of AN8 standard. I also got some very kind and precious advice from Jeff-Godzilla and I want to thank you all: this reading has been a thrilling experience, leading me to learn a lot on speaker building and hi-fi in general. I wish I had known this forum before building my actual cabinets... (if I think of the time it took me the finishing of those cabinets... I won't build a new couple!).
I still have some doubts and I hope that some one can help me. As I have not read the full thread it is possible that some of this has already been answered - I bag your pardon for this.
1) I found differences between the size of Sm calculated with the BIB calculators (=133"^2) and the measures provided by Godzilla in his site (168"^2). Why does this happen? Is there a reason to use a larger Sm?
2) In the formula to calculate Sm there is a value (1728 imperial, that is 12^3; 61.0237 metric) - where does this come from?
3) Stuffing - maybe this is the real "newbie" question, very naif... but how do I keep in place the stuffing above and around the driver? Won't it fall down? I hope the question is not too silly!
4) Apart from tcrane (post #4294) did anybody measure BIB performance? If so, do measures fit with the model or not? that would one of the most interesting things to know.
5) Suprabaffle question. For various reasons, I think I will do something similar to what Godzilla did: a large wooden rectangular panel, all over the front baffle. What if I mounted it in such a way that the speaker were not centered? Could it be useful?
I will test my cabinets with a Trends TA10.1 + Promitheus TVC passive pre, with a NAD 3220PE and, hopefully soon, with a VirtueAudi😵NE.
A huge thank you, for the pleasure I got reading this thread and for the replies to all my questions.
Guido
I found a little spare time and decided to add some fotos of my BIBs!
The drivers are allready broke in and now I'm doing some stuffing experiments.
Here are some shots:
The woods with some of the veneer...
Adding the brace....
Glueing together! The double front and back are added after this step.
The BIBs with suprabaffle, ready for oil-finishing... ok after a little sanding.
And a complete BIB with FE168ES in the listening room!
They're a little bit more yellowish after the oil-finish. But they look great. I love them!
And sound even greater! A big thanks to Scottmoose, Planet10, GM, Godzilla and of course to Mr. Terry Cain! Too bad we don't have him with us....
The drivers are allready broke in and now I'm doing some stuffing experiments.
Here are some shots:
The woods with some of the veneer...
Adding the brace....
Glueing together! The double front and back are added after this step.
The BIBs with suprabaffle, ready for oil-finishing... ok after a little sanding.
And a complete BIB with FE168ES in the listening room!
They're a little bit more yellowish after the oil-finish. But they look great. I love them!
And sound even greater! A big thanks to Scottmoose, Planet10, GM, Godzilla and of course to Mr. Terry Cain! Too bad we don't have him with us....
I just built one!
The driver is a 3" Omnes BB 3.01, and it's in a nice two meter tall BIB made out of ... expanded polystyrene!
Holy hell it sounds good.
It's just taped together right now, and the panels are squeaking against each other and leaking air, and there's no damping, and still it sounds beautiful.
The expressions on my flatmates were priceless - a mixture of confusion and pleasure. "Yes," they said, "there really is a piano in the corner!"
Can't wait to finish them properly with glue and damping and the rest. Thanks everybody! Thanks thanks thanks.
The driver is a 3" Omnes BB 3.01, and it's in a nice two meter tall BIB made out of ... expanded polystyrene!
Holy hell it sounds good.
It's just taped together right now, and the panels are squeaking against each other and leaking air, and there's no damping, and still it sounds beautiful.
The expressions on my flatmates were priceless - a mixture of confusion and pleasure. "Yes," they said, "there really is a piano in the corner!"
Can't wait to finish them properly with glue and damping and the rest. Thanks everybody! Thanks thanks thanks.
The BIBs are especially appreciative of piano.
Would like to see some more pics. All I see is foam of some sort.
Wait. Did you say the sides were squeaking? That gives me the willys like scraping on a blackboard.
😉
Would like to see some more pics. All I see is foam of some sort.
Wait. Did you say the sides were squeaking? That gives me the willys like scraping on a blackboard.
😉
Hi,
I'll try to get some pictures online.
Here's a couple thoughts ...
This is how I currently like to listen to the one BIB I've got running. I assume that a sturdier, airtight box will give me more bass naturally. I also assume that I'll need to stuff a bit more to fix the midrange. Anything else you guys would start with to try to fix the frequency skew at the enclosure level?
I'll try to get some pictures online.
Here's a couple thoughts ...
An externally hosted image should be here but it was not working when we last tested it.
This is how I currently like to listen to the one BIB I've got running. I assume that a sturdier, airtight box will give me more bass naturally. I also assume that I'll need to stuff a bit more to fix the midrange. Anything else you guys would start with to try to fix the frequency skew at the enclosure level?