On top of that I just used..."Ach" I thinking I'm getting way too comfortable with German language and expressions....
Yeah you're right... I mean I can't do anything else! Besides there is a saddistic part of you that gets involved, when you truly love what you do and it means so much to you....everything you do the ups and downs are magnified and somehow dictate your outlook on life, for that day. (or financially for that month!) Money comes and goes its like the tides I guess. I can't complain though there are many people much worse off. Besides next month will be better! Anyone else find february a killer for finances?!
Speaker building and hifi in general is a great way to switch off!
Stroop
Speaker building and hifi in general is a great way to switch off!
Stroop
stroop said:
If anything like my earlier scratch builds, count your blessings that finances stretch the project out over many months; you'll "learn" enough to change your mind more than once - and relish the final results all that much more.
Well, I'm finally going to go for it and build the BIB's for my FE206ES-R's, but I have some questions...
First, according to the BIB info on the zillaspeak site, the area of the terminus is supposed to be 139.125 square inches, so I calculate the closest I can get to a 1 X 1.4142 ratio with increments of 1/8" is 9 and 7/8" by 14". Is this correct and the correct ratio?
Second, would it be overkill to line the entire interior with 1/8" cork, and should that be taken into consideration when figuring out the interior dimensions? In other words, does the cork count as solid wood, or is it ignored like stuffing?
I plan on experimenting with stuffing the area above the driver and trying a deflex pad behind it, but those can be easily removed, whereas the cork cannot.
Do I remember correctly when I recall that the bottom, back and dividing panel should be made of lossy material like particle board, while the sides and front panel should be stiff material like 3/4" void free ply? Is the lossy material meant for sound absorbing or vibration absorbing?
Sorry for the questions, but I've read this entire thread all the way through twice before and have done plenty of searches, but since several people have built the BIB's over all this time, I really, really want suggestions, particularly from people that have made the BIB's with larger drivers.
So... Answers? Advice? Suggestions?
🙂
First, according to the BIB info on the zillaspeak site, the area of the terminus is supposed to be 139.125 square inches, so I calculate the closest I can get to a 1 X 1.4142 ratio with increments of 1/8" is 9 and 7/8" by 14". Is this correct and the correct ratio?
Second, would it be overkill to line the entire interior with 1/8" cork, and should that be taken into consideration when figuring out the interior dimensions? In other words, does the cork count as solid wood, or is it ignored like stuffing?
I plan on experimenting with stuffing the area above the driver and trying a deflex pad behind it, but those can be easily removed, whereas the cork cannot.
Do I remember correctly when I recall that the bottom, back and dividing panel should be made of lossy material like particle board, while the sides and front panel should be stiff material like 3/4" void free ply? Is the lossy material meant for sound absorbing or vibration absorbing?
Sorry for the questions, but I've read this entire thread all the way through twice before and have done plenty of searches, but since several people have built the BIB's over all this time, I really, really want suggestions, particularly from people that have made the BIB's with larger drivers.
So... Answers? Advice? Suggestions?
🙂
BHD said:
Don't forget to add the thickness of your internal baffle... so if you use 3/4" ply the external dimension would be 9 7/8 + 1 1/2 = 11 3/8 by !4 + 2 1/4 = 16 1/4"
I would count the cork as wood.
dave
Greets!
Well, I've built similar floor loaded pipes decades ago with up to 15" drivers, but no BIBs per se, though that hasn't stopped me from voicing my opinions on occasion. 😉
It's a ratio I like since it ~preserves the area expansion through the bend, but neither the original nor many of the early BIBs built do and no one's complained AFAIK, so nothing to lose sleep over. Ditto the base area accuracy. I would have rounded them up to the nearest 1/10 just because I have a tape measure with 10ths, but rounding up to the next common fraction yields 14.125" x 9.94", or even 10" is close enough.
I experimented a bit with cork a long time ago and its BW absorption was so high compared to other materials of similar thickness that I didn't see the point, but if you use it I recommend increasing the pipe dims by ~its thickness. The thicker, decorative tiles make a nice baffle veneer in the right room decor though and helps with damping any HF early reflections.
Yeah, I mentioned using a more lossy material for at least the internal baffle board/bottom and if it's backed up hard against a wall, then the rear panel, and if hard into a corner, then you can make the side in the corner lossy also, but I mean right up against it, not spaced away by a baseboard/whatever. It's for any spurious vibrations from ~400 Hz - up. If it's ~free standing then I recommend 3/4" (19 mm) no-void plywood or at least a very rigid/stable hardwood such as I listed ~recently.
GM
Well, I've built similar floor loaded pipes decades ago with up to 15" drivers, but no BIBs per se, though that hasn't stopped me from voicing my opinions on occasion. 😉
It's a ratio I like since it ~preserves the area expansion through the bend, but neither the original nor many of the early BIBs built do and no one's complained AFAIK, so nothing to lose sleep over. Ditto the base area accuracy. I would have rounded them up to the nearest 1/10 just because I have a tape measure with 10ths, but rounding up to the next common fraction yields 14.125" x 9.94", or even 10" is close enough.
I experimented a bit with cork a long time ago and its BW absorption was so high compared to other materials of similar thickness that I didn't see the point, but if you use it I recommend increasing the pipe dims by ~its thickness. The thicker, decorative tiles make a nice baffle veneer in the right room decor though and helps with damping any HF early reflections.
Yeah, I mentioned using a more lossy material for at least the internal baffle board/bottom and if it's backed up hard against a wall, then the rear panel, and if hard into a corner, then you can make the side in the corner lossy also, but I mean right up against it, not spaced away by a baseboard/whatever. It's for any spurious vibrations from ~400 Hz - up. If it's ~free standing then I recommend 3/4" (19 mm) no-void plywood or at least a very rigid/stable hardwood such as I listed ~recently.
GM
GM said:
I'll try to get it as accurate as possible.
I just want to be sure, does "BW" above mean back wave? It's not for damping, it's more to absorb the high frequencies so they don't come out of the top. 1/8" isn't going to damp much anyway (or will it?). I like the idea of cork on the outside of the front baffle, but I don't think I'll try it this time. With you and Dave both suggesting compensating for the thickness of the cork, that's definitely going to happen. I'm thinking of using 1/2" particle board for the internal baffle, covered in 1/8" cork on both sides to bring the thickness up to 3/4". My only concern about covering the entire inside of the horn with it is that it'll be too much. Oh well, we'll see I guess.
The speakers will be on either side of my fireplace, hopefully looking like two really cool pillars! 😎 They will, however, be about three inches away from the back wall because of hot water baseboard radiators. I should also mention that I have people living below me, so should I only use particle board for the internal baffle and have all the outer walls made of 3/4" ply, or should I still keep the bottom particle board?
Thanks for all the help guys, I see a plan coming together and these suckers are gonna get built!
I recently saw these:
http://www.asparaacoustics.co.uk/hl2_concept.php
Uses a helper dome tweet for the small FR. I may be wrong, but it looks like a variation of an Inverted BIB. What's intresting is the curved slot on one side by the mouth exit.
fred
http://www.asparaacoustics.co.uk/hl2_concept.php
Uses a helper dome tweet for the small FR. I may be wrong, but it looks like a variation of an Inverted BIB. What's intresting is the curved slot on one side by the mouth exit.
An externally hosted image should be here but it was not working when we last tested it.
fred
planet10 said:
Greets!
Seems I've explained this before, but FWIW with the 1:1.4142 ratio you don't add the baffle thickness to the depth dim if it's built the same as shown on TC's drawing and/or the baffle board is angle cut to mount flush to the rear of the front baffle as it changes the line length. Not that it really matters with BIBs though.
GM
BHD said:
Greets!
You're welcome!
BW = bandwidth, as in the BW the material is most effective at absorbing reflections and/or damping vibrating panels. Obviously, 1/8" will only do HF, which should have already been damped down long before it reaches the mouth.
Theoretically, lining the entire pipe is a good thing since it mass loads it, but the downside is it may sound 'dull' due to 'sucking the life' out of the driver's output. The trick is getting the right amount of trade-off.......
I'd use it for both the internal baffle and bottom and add cork on the bottom if you don't have carpet+padding.
GM
I just used the stuffing of an old bed-quilt, lined the sloped baffle from the top, behind the driver, and a bit around the bottom end/back side of it.loninappleton said:
Fold a piece of it (double or triple) and put it at the bottom.
I'll try to tame, as you say, the hf leak, as I think they're too harsh. There's really nice lows coming out, but the mid-highs are dominating.
Could be the room as well,a s it's a rather large room --> Too big for these (Or too small speakers... ooops.. sorry wife.. but I have to make another pair... 😀 )
The room's like 8x4 meters, and the speakers are (== have to be...) along the long side of it. Very hard wall's (most of them) and a verrrry hard/refecting floor, and french doors etc.. Far from Ideal.
(See here )
I'll shove my system into the bedroom one of these days, just to see what it's able to do in a more appropriate room.
Cheers, Bibster
I would say, experiment with different materials until you iron things out. Every build will be slightly different and therefore require different treatments. As far as I am concerned no material is out of bounds. All our solutions are going to be what we personally find when we listen to OUR own build.
I have been mucking around for about 2 months now (loving it by the way!) with different materials. Its funny each material has a different sound character to it. Bubble wrap was good, but not as a complete solution. I found in my case thin felt to be better than thick etc. etc. I have about three different materials in mine somewhere and they sound pretty darn good now. I want to try cardboard ribbing.
Oh (edit) lining all hard surfaces behind the driver 6 inches above and below with thin felt made the highs and mids in mine much clearer and more subtle. Everything you do can be heard better or worse!
I found exactly that GM, lining the whole length took a bit of the dynamic/excitement away. Using materials that disperse high frequencies give me a better result.
Cheers Stroop
I have been mucking around for about 2 months now (loving it by the way!) with different materials. Its funny each material has a different sound character to it. Bubble wrap was good, but not as a complete solution. I found in my case thin felt to be better than thick etc. etc. I have about three different materials in mine somewhere and they sound pretty darn good now. I want to try cardboard ribbing.
Oh (edit) lining all hard surfaces behind the driver 6 inches above and below with thin felt made the highs and mids in mine much clearer and more subtle. Everything you do can be heard better or worse!
I found exactly that GM, lining the whole length took a bit of the dynamic/excitement away. Using materials that disperse high frequencies give me a better result.
Cheers Stroop
Hi BHD!
With the size of your BIB's, I would recommend to have a detachable bottom. My mouth area is around 55 square inches and I've been able to change damping quite easily, from the driver and down to bottom. Later when you are satisfied you can always glue them permanently, however mine are still screwed and with window sealer against leakage.
Good luck
Peter
With the size of your BIB's, I would recommend to have a detachable bottom. My mouth area is around 55 square inches and I've been able to change damping quite easily, from the driver and down to bottom. Later when you are satisfied you can always glue them permanently, however mine are still screwed and with window sealer against leakage.
Good luck
Peter
Attachments
Godzilla said:
I had a bottom that is removable as well but failed to mention
in the last series of posts in this thread. I took bottom off, put
on a couple layers of fiber fill and loosely attached it in place with
one inch fine brads so as not to compact it.
For around the mouth, I'm wondering if egg crate foam (the sort
used to baffle walls in sound studios) would be more effective (?)
Also are there any tips on what to listen for at the terminus? As something is playing is there a way to know what to hear and
how to tune for it?
Hi Lon
I tried to listen for anything but it is just too difficult... I reckon just do it from the listening position. I just got too confused they other way.
I'd love to try that stuff too. Could be interesting! I might try squashing some egg cartons...anything goes. No harm in trying it. It also helps that I don't have to remove anything with my pipes. Just take the driver out and reach in. You'll notice when something good happens because the imaging clears up and you (well I did) get a clarification of instruments etc.
I found that dispertion of high frequencies was better than trying to absorb them. It inevitably happens that something happens to middle and deep frequencies as well that I didn't like.
Oh and get your other half to help out with the listening test. Mine has a unique nack of telling me what's what. Women also hear higher frequencies better than men. (on average)
Stroop
I tried to listen for anything but it is just too difficult... I reckon just do it from the listening position. I just got too confused they other way.
I'd love to try that stuff too. Could be interesting! I might try squashing some egg cartons...anything goes. No harm in trying it. It also helps that I don't have to remove anything with my pipes. Just take the driver out and reach in. You'll notice when something good happens because the imaging clears up and you (well I did) get a clarification of instruments etc.
I found that dispertion of high frequencies was better than trying to absorb them. It inevitably happens that something happens to middle and deep frequencies as well that I didn't like.
Oh and get your other half to help out with the listening test. Mine has a unique nack of telling me what's what. Women also hear higher frequencies better than men. (on average)
Stroop