Hi Ioninappleton
Thanks for the reply.Actually I found the calculator etc. - however I also found the woofer page,where it says to cut them at around 80hz.
However what I had in mind was a "standard" 2-Way-possibly with a waveguide integrated in the "supra baffle".
I realize this is a fullrange thread,but was just wondering if anyone had tried a 2-way solution,as I´m not especially fond of the fostex-sound.
It was the cabinet design + placement (corner/against backwall) that I liked.
The Woodwork etc. is not a problem.Might give it a go still.
Brgds Mikael.
Thanks for the reply.Actually I found the calculator etc. - however I also found the woofer page,where it says to cut them at around 80hz.
However what I had in mind was a "standard" 2-Way-possibly with a waveguide integrated in the "supra baffle".
I realize this is a fullrange thread,but was just wondering if anyone had tried a 2-way solution,as I´m not especially fond of the fostex-sound.
It was the cabinet design + placement (corner/against backwall) that I liked.
The Woodwork etc. is not a problem.Might give it a go still.
Brgds Mikael.
double baffle opening
No action in this thread in a while so maybe this will start some discussion.
I am not using a supra baffle after trying one on my bib. I chamfered both baffle and supra baffle opening such that it was a smooth angle to the interior. I still didn't like what I felt was a pinched sound.
I know that very thing supra baffles have been used and after this length of time has anybody noticed a similar problem?
To return to supra baffle use would a largely increased opening on the main baffle cure such a problem? In other words, get as much air into the opening as possible. I've always like the idea of the supra baffle tweak and then started thinking about how the "tunnel problem" could be alleviated.
No action in this thread in a while so maybe this will start some discussion.
I am not using a supra baffle after trying one on my bib. I chamfered both baffle and supra baffle opening such that it was a smooth angle to the interior. I still didn't like what I felt was a pinched sound.
I know that very thing supra baffles have been used and after this length of time has anybody noticed a similar problem?
To return to supra baffle use would a largely increased opening on the main baffle cure such a problem? In other words, get as much air into the opening as possible. I've always like the idea of the supra baffle tweak and then started thinking about how the "tunnel problem" could be alleviated.
OK, I may not quite answer your question but I will share my findings.
When I first listened to my BiBs (FE168EZ) I thought there was a mid-range zealous, pinched sound and was slightly disappointed. I also knew that the drivers needed to burn for longer so I was patient.
It payed off in my case. Bass (very low and mid bass) filled out to give real body to the sound and the top end was good but was transformed recently when I added some silver internal wiring - now they have real shimmer and no glare at all.
I do find that on some tracks (due to the recordings) lower female, close mic'd vocals can protrude a bit (un-naturally) but it is always room and recording dependent. I have a friend with a different system and his have no mid-range protrusion at all but are a bit bright for my tastes wit his electronics.
Having lived with my Bibs for 3 years I am still very satisfied and still surprised by new music. They are not 100% prefect but are so easy to make and so rewarding that a build is a no-brainer.
Hope this helps a bit?
When I first listened to my BiBs (FE168EZ) I thought there was a mid-range zealous, pinched sound and was slightly disappointed. I also knew that the drivers needed to burn for longer so I was patient.
It payed off in my case. Bass (very low and mid bass) filled out to give real body to the sound and the top end was good but was transformed recently when I added some silver internal wiring - now they have real shimmer and no glare at all.
I do find that on some tracks (due to the recordings) lower female, close mic'd vocals can protrude a bit (un-naturally) but it is always room and recording dependent. I have a friend with a different system and his have no mid-range protrusion at all but are a bit bright for my tastes wit his electronics.
Having lived with my Bibs for 3 years I am still very satisfied and still surprised by new music. They are not 100% prefect but are so easy to make and so rewarding that a build is a no-brainer.
Hope this helps a bit?
I guess so. It is certainly worth trying if you can make an oval supra baffle easily. I found that the thickness of the baffle itself makes a difference to the 'air' in the sound. Essentially, placing the driver's plane further out from the air chamber thereby allowing for more material to be removed behind it (creating a larger opening to the main cabinet) seemed to let the driver breathe a bit more.
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Hi Lon,
Hmm. If I recall correctly, GM said once that as long as the opening into the BiB's interior is at 45 degrees, that's enough to avoid any "tunnel resonance".
If the sound is "pinched" with the supra-baffle, it could be a lot of things. The supra-baffle has to cure a very specific dip in the response, so width is the critical dimension, and if you don't have the dip that corresponds to the supra-baffle's width, it ends up being detrimental to a flat response.
Another possibility is that the supra-baffle adds a lot of strength to the baffle, and eliminates a lively cabinet, causing it to sound "deader" which in this exact case, for your tastes and room etc., could be a step back?
I have BiB's made for the FE166ES-R's which are going to get a hasty, un-beautiful retrofit to take the Jordan JX92S just as a quick and dirty way to hear the drivers. I'm adding a cab-width baffle plate to get the smaller Jordan into the bigger hole, and I'm hoping there will be improved baffle strength to handle the Jordan's vastly greater excursion. If it works out half-decently, I'll build a more correct BiB for the Jordans. I'm searching for the "ultimate BiB" and GM was kind enough to send me some pointers (thank you, GM!)
Hmm. If I recall correctly, GM said once that as long as the opening into the BiB's interior is at 45 degrees, that's enough to avoid any "tunnel resonance".
If the sound is "pinched" with the supra-baffle, it could be a lot of things. The supra-baffle has to cure a very specific dip in the response, so width is the critical dimension, and if you don't have the dip that corresponds to the supra-baffle's width, it ends up being detrimental to a flat response.
Another possibility is that the supra-baffle adds a lot of strength to the baffle, and eliminates a lively cabinet, causing it to sound "deader" which in this exact case, for your tastes and room etc., could be a step back?
I have BiB's made for the FE166ES-R's which are going to get a hasty, un-beautiful retrofit to take the Jordan JX92S just as a quick and dirty way to hear the drivers. I'm adding a cab-width baffle plate to get the smaller Jordan into the bigger hole, and I'm hoping there will be improved baffle strength to handle the Jordan's vastly greater excursion. If it works out half-decently, I'll build a more correct BiB for the Jordans. I'm searching for the "ultimate BiB" and GM was kind enough to send me some pointers (thank you, GM!)
rjbond,
there you are. In both cases. Leave enough "flesh" where the screws have to hold and chamfer like hell everywhere else.
As to the baffle - Edge. A p.i.t.a. insofar as it doesn´t accept measured FR, you have to mentally add the baffle response to your driver´s - but you can input your baffle shape by click-and-pull...watching the result side by side with the driver response gets you there.
TC was a hands-on man and had a workplace to dream of, so he never needed sims. Quote: "I´m allowed to use good tools after hours - I own the place"
there you are. In both cases. Leave enough "flesh" where the screws have to hold and chamfer like hell everywhere else.
As to the baffle - Edge. A p.i.t.a. insofar as it doesn´t accept measured FR, you have to mentally add the baffle response to your driver´s - but you can input your baffle shape by click-and-pull...watching the result side by side with the driver response gets you there.
TC was a hands-on man and had a workplace to dream of, so he never needed sims. Quote: "I´m allowed to use good tools after hours - I own the place"
The assumption here is that the supra baffle gets at least a 45 deg chamfer and the cab's baffle gets a hole that's of the same size as what's on the backside of the supra baffle, then cut at an angle also, i.e. ideally clamp the two together to make the chamfer before any cab assembly. For adding a supra baffle to a completed cab, just mount the supra baffle and use it as a guide to blend the two. It doesn't need to be all that smooth, so a wood rasp or rasp bit on a drill or heavy duty hand grinder is good enough and makes short work of all but the hardest woods.
You're welcome! Looking forward to what you wind up with.
GM
Everybody?! You haven't seen how little/no disposable income me and most of my friends, etc. around my age have had since shortly after 9/11 plus IME it takes a fairly heavy duty/powerful router wielded by someone with a very good grip and forearm strength to free hand with a ~1.5" chamfer bit without destroying the workpiece(s).
Of course if folks have the means, inclination, this is certainly the quickest way to get the job done AFAIK, but to me it seems a 'recipe for disaster' for the average DIYer unless they make a router guide which by the time they were ready to 'burn wood', I'd already long since finished with a hand rasp. Wouldn't look nearly as nice obviously, but it in theory will work better due to being both irregular in shape and grooved for faster decay of any HF
GM
I did mine by hand with a sureform, rasp and sand paper. I really enjoyed the time it took, gently shaping. I did flare the inside to continuously expand rather than just angle at 45 degrees, but that might have been over-kill
Yeah, if the material isn't too hard, a SurForm file is my tool of choice, though for reasons just posted I don't waste any time sanding except to deal with any plywood splinters.
Yeah, ideally an expanding flare that begins at least 45 deg or the inverse of the driver diaphragm's to create at least a 90 deg included angle, but we're 'splitting hairs' here, so rounding over the edge of the 45 deg chamfer is all I recommend.
FWIW, historically I haven't used a router to cut driver holes, so for built up baffles I just made two different size holes and lined the 'step' with damping material to create a pseudo 'infinite' flare.
GM
>>> Having lived with my Bibs for 3 years I am still very satisfied and still surprised by new music. They are not 100% prefect...
Has it been this long? I can't believe i just went to my 25th (it's actually been 27) year high school reunion. Three years is a long time to own a speaker imo, especially a DIY speaker. I can't go several months before wanting to try something different. My basement adorns with unused cabinets from Straight Pipes, various sized ported, H-frames and even BIBs! I even have un built boxes labeled and piled as planks (unfortunately some of these panels have warped over time - home depot stock, grrr)... A couple of people at the reunion told me they still have speakers i built for them over 25 years ago... but most said they put them in the trash after about 20 years. Imagine 20 years from now BIB's standing tall out for trash, young audiophiles having read our threads, restoring and fitting them with modern drivers, adding tube amps and a turntable.
Godzilla
Has it been this long? I can't believe i just went to my 25th (it's actually been 27) year high school reunion. Three years is a long time to own a speaker imo, especially a DIY speaker. I can't go several months before wanting to try something different. My basement adorns with unused cabinets from Straight Pipes, various sized ported, H-frames and even BIBs! I even have un built boxes labeled and piled as planks (unfortunately some of these panels have warped over time - home depot stock, grrr)... A couple of people at the reunion told me they still have speakers i built for them over 25 years ago... but most said they put them in the trash after about 20 years. Imagine 20 years from now BIB's standing tall out for trash, young audiophiles having read our threads, restoring and fitting them with modern drivers, adding tube amps and a turntable.
Godzilla
Hmm, how does rounding over the edge of a chamfered mounting hole make it look like it 'belonged'? I mean we've been talking about the backside of a front mounted driver, so I assume you're referring to rounding over the baffle face for a rear mounted driver which for a wide BW one is a good plan acoustically since it will keep eigenmodes from forming and amplifying those already being generated across the driver and why foam rings inserted in the cavity created by the gasket is a nice, subtle tweak. Ditto to cover it when front mounted.
Regardless, sounds like a nice 'warm' room. Got any photos?
GM
Regardless, sounds like a nice 'warm' room.
Got any photos? GM
Misunderstanding of my comment. I meant that the choice of timber to match other timber in my room made the speakers look like the belonged there. I live in an old place (c1650) and the front supra baffle in elm was an aesthetic decision.
I only built a very simple single driver BiB using the 6.5" Fostex and birch ply, pretty standard fare.
I can try to find an image somewhere and work out how to post it...
I only built a very simple single driver BiB using the 6.5" Fostex and birch ply, pretty standard fare.
I can try to find an image somewhere and work out how to post it...
GM - sorry. I keep forgetting that we have quite an international bunch of friends here and prices differ. In Germany everybody considers himself a skilled craftsman, so even large food stores have power tools as "bait" offers. A router, sander, drill, hand saw made by Bosch for less than €40...you just have to read the ads to find them. Mind - your feeling about an irregularly shaped chamfer...yup. Hadn´t thought of that.
