Thanks EEatKSU, what is your estimate of the max SPL that your pair may reach? And do the drivers reach their Xmax prior to full power loading? Did you include HF drivers?
Thanks for any inputs,
Thanks for any inputs,
Theres a thread of pictures floating somewhere around here, there might be a link a couple pages back in this thread.
Max SPL: ******** insanely loud in my house, talking pull my QSC Powerlight 1.0HV down, ear plugs, and it will take all of it. Doesn't sound as good but it does take it.
Xmax: It really all depends on what you are listening to, if you are listening to bass heavy songs it will reach Xmax with a lot lower power than otherwise. Needless to say when you reach Xmax you should really be wearing earplugs for any amount of time.
HF: I have the Fostex FT17 tweeter on there and it seems to work alright, haven't blown it yet with ridiculous amounts of power so it holds up decently well. I can't remember what I have on it for a crossover but it isn't very ideal at all.
If you want to build these, there are a couple things you should do first.
Make sure you have room to put them, they are MASSIVE.
Make sure you have a full size truck to movie them.
Make sure you have friends to help, I can move them by myself but it is NOT fun.
If you like 'real' sounding music at a high volume, these could easily be the speakers for you. They sound fantastic to me, very musical and dynamic. The ceilings in my upstairs are ~9' tall and I'd imagine taller ceilings wouldn't be a problem at all. If you need two speakers for a rave and have a limited budget, these are definitely the thing. My roommate loves techno and these things preform them admirably. Normally I power them with an older Yamaha receiver and they sound excellent with the lesser power, and you definitely don't need a rack amp but more power has never hurt anyone.
Max SPL: ******** insanely loud in my house, talking pull my QSC Powerlight 1.0HV down, ear plugs, and it will take all of it. Doesn't sound as good but it does take it.
Xmax: It really all depends on what you are listening to, if you are listening to bass heavy songs it will reach Xmax with a lot lower power than otherwise. Needless to say when you reach Xmax you should really be wearing earplugs for any amount of time.
HF: I have the Fostex FT17 tweeter on there and it seems to work alright, haven't blown it yet with ridiculous amounts of power so it holds up decently well. I can't remember what I have on it for a crossover but it isn't very ideal at all.
If you want to build these, there are a couple things you should do first.
Make sure you have room to put them, they are MASSIVE.
Make sure you have a full size truck to movie them.
Make sure you have friends to help, I can move them by myself but it is NOT fun.
If you like 'real' sounding music at a high volume, these could easily be the speakers for you. They sound fantastic to me, very musical and dynamic. The ceilings in my upstairs are ~9' tall and I'd imagine taller ceilings wouldn't be a problem at all. If you need two speakers for a rave and have a limited budget, these are definitely the thing. My roommate loves techno and these things preform them admirably. Normally I power them with an older Yamaha receiver and they sound excellent with the lesser power, and you definitely don't need a rack amp but more power has never hurt anyone.
here's the link to the post that shows them.
https://www.diyaudio.com/community/threads/bbbib-bigger-badder-bib-speaker.88104/post-1266924
https://www.diyaudio.com/community/threads/bbbib-bigger-badder-bib-speaker.88104/post-1266924
Last edited by a moderator:
EEatKSU said:
FWIW, my 20 ft^3 cabs calc ~245 lbs, so I added a well reinforced grab handle along with casters at the bottom rear to easily move them around by myself and later added two 2x4 skids on the rear to both stiffen it and allow me to 'slide' them up/down stairs.
WRT using them as party speakers, stretching the budget to dual drivers/channel and high power amp to isobarically load them to reduce size/weight and increase power handling down low where the BIB needs it seems a very worthwhile initial sacrifice.
GM
So finally a friend of mine is cutting the wood for one of these.
BUT we referred to the crossover that Panomaniac mentioned and it really never got finished as even theoretical values weren't mentioned for the tweeter..
Coincidently I have a pair of the Fostex FT 17 tweeters EEat KSU used so I suppose that I'll try them. I think he said that he used a second order active crossover? I'm gong to look at Partsexpress and see if there are any other candidates. While the tweeter looks pretty flimsy, he hasn't blown it up, and it does have an advantage that it goes well beyond 20khz flat...
Here's the link to our discussion about crossovers
http://www.diyaudio.com/forums/showthread.php?postid=1040927#post1040927
I think that Panomaniac wanted to cut off the woofer a bit low to avoid its frequency bump..and the FT 17 wants at LEAST 5k for a crossover... Or the old helper tweeter approach of about 1.5uF might be OK, but the woofer midbump will remain..
Pano recommended single inductor I'm thinking at about 700Hz?
That should flatten things out. Once the woofer runs out of steam, it rolls itself off so really won't require an additional low pass filter
is about 1.3mH right for this?
looks like he was looking at about 1 mH
Here is the tweeter Datasheet:
http://www.madisound.com/catalog/PDF/fostexdrivers/ft17h.pdf
Here is the 12" spec sheet
http://www.partsexpress.com/pdf/290-409s.pdf
Pano, you out there?
BUT we referred to the crossover that Panomaniac mentioned and it really never got finished as even theoretical values weren't mentioned for the tweeter..
Coincidently I have a pair of the Fostex FT 17 tweeters EEat KSU used so I suppose that I'll try them. I think he said that he used a second order active crossover? I'm gong to look at Partsexpress and see if there are any other candidates. While the tweeter looks pretty flimsy, he hasn't blown it up, and it does have an advantage that it goes well beyond 20khz flat...
Here's the link to our discussion about crossovers
http://www.diyaudio.com/forums/showthread.php?postid=1040927#post1040927
I think that Panomaniac wanted to cut off the woofer a bit low to avoid its frequency bump..and the FT 17 wants at LEAST 5k for a crossover... Or the old helper tweeter approach of about 1.5uF might be OK, but the woofer midbump will remain..
Pano recommended single inductor I'm thinking at about 700Hz?
That should flatten things out. Once the woofer runs out of steam, it rolls itself off so really won't require an additional low pass filter
is about 1.3mH right for this?
looks like he was looking at about 1 mH
Here is the tweeter Datasheet:
http://www.madisound.com/catalog/PDF/fostexdrivers/ft17h.pdf
Here is the 12" spec sheet
http://www.partsexpress.com/pdf/290-409s.pdf
Pano, you out there?
Hi Variac
Just to recap my recent email to you - for the benefit of the forum readers.
Since the original post I've worked a bit with fullrange drivers and tweeters/super tweeters. My thought now would be to keep it simple.
The Fostex looks like it would work well because it's close the the same sensitivity as the Beta LTA. It will need to be brought down a little, maybe 4dB. That can be done with a series resistor or an L-pad. Or by using a cap that is "too small" (1st order). The too small cap trick works well and is simple.
As for the Beta 12LTA, I think just find a coil value that will roll it off above about 6Khz. As that will be first order, the LTA will still contribute right on up. But the Fostex can take over on the top.
It should be possible to stay simple, no Zobel or traps needed.
However, John Wyckoff used a much more complex crossover in his Hammer Dynamic (reconed 12LTA). 1st order with Zobel and trap on the 12, 3rd order on the tweeter.
TBD.
Just to recap my recent email to you - for the benefit of the forum readers.
Since the original post I've worked a bit with fullrange drivers and tweeters/super tweeters. My thought now would be to keep it simple.
The Fostex looks like it would work well because it's close the the same sensitivity as the Beta LTA. It will need to be brought down a little, maybe 4dB. That can be done with a series resistor or an L-pad. Or by using a cap that is "too small" (1st order). The too small cap trick works well and is simple.
As for the Beta 12LTA, I think just find a coil value that will roll it off above about 6Khz. As that will be first order, the LTA will still contribute right on up. But the Fostex can take over on the top.
It should be possible to stay simple, no Zobel or traps needed.
However, John Wyckoff used a much more complex crossover in his Hammer Dynamic (reconed 12LTA). 1st order with Zobel and trap on the 12, 3rd order on the tweeter.
TBD.
I'm trying to work up a crossover for the BBBIB with the Beta 12LTA and Selenium slot tweeter. This will be a starting point only, as I'll be going by published specs, not by ear or measurements.
Another very good starting point for the Beta LTA would be to read Dick Olsher's artice on the Hammer Dynamic. Basically the same driver.
Another very good starting point for the Beta LTA would be to read Dick Olsher's artice on the Hammer Dynamic. Basically the same driver.
thanks for taking this on. I feel it will help future builders get a starting place at least... But mostly I thinkin' - it will help me!!
Welll I tried and tried to come up with a nice, simple crossover for this (on paper).
But it's not happening.
My best advice is to go with the Hammer Dynamic X-over for the Beta LTA and about 2uF on the Selenium tweeter.
That means a 6 element crossover for the LTA and 1 element for the tweeter. Not the most simple, but it could be worse.
Perhaps you could leave out the RLC trap filter on the LTA to begin with, but I'll bet you're going to want it.
But it's not happening.
My best advice is to go with the Hammer Dynamic X-over for the Beta LTA and about 2uF on the Selenium tweeter.
That means a 6 element crossover for the LTA and 1 element for the tweeter. Not the most simple, but it could be worse.
Perhaps you could leave out the RLC trap filter on the LTA to begin with, but I'll bet you're going to want it.
Well, I whipped together an idea with an inductor on the woofer to tame the rising mids, and a second order on the tweeter corresponding to where the woofer rolls off and we'll see...
Actually Nelson, (not Pass!) the guy making this, has put the crossover together and says its OK. I haven't heard it yet. I hope he posts here with some pics soon...
Actually Nelson, (not Pass!) the guy making this, has put the crossover together and says its OK. I haven't heard it yet. I hope he posts here with some pics soon...
thanks to variac and many hours in the shop, my pair is done!
some pictures:
i tested them using some questionable materials (like romex) but they sounded very good
today i will be bringing in some better equipment and re-listen to them
some pictures:
i tested them using some questionable materials (like romex) but they sounded very good
today i will be bringing in some better equipment and re-listen to them
Here's the tweeter:
http://www.partsexpress.com/pdf/264-360.pdf
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-360&ctab=2#Tabs
Way to go N-Brock!!
If you guys remember, we designed these BBBIB's for a youthful Mr. Punkrockr a while back who wanted lots of bass. Mr. N-Brock is about the same age as Punkrockr, so finally the design has accomplished its intended goal.. Rock On!😱
http://www.partsexpress.com/pdf/264-360.pdf
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-360&ctab=2#Tabs
Way to go N-Brock!!
If you guys remember, we designed these BBBIB's for a youthful Mr. Punkrockr a while back who wanted lots of bass. Mr. N-Brock is about the same age as Punkrockr, so finally the design has accomplished its intended goal.. Rock On!😱
Fantastic! I would like to put some of your pics on the BIB website. May I?
Here's the latest BIB calculator:
http://www.zillaaudio.com/bib-calculator.htm
Godzilla
PS. I think your driver combo is great!
Here's the latest BIB calculator:
http://www.zillaaudio.com/bib-calculator.htm
Godzilla
PS. I think your driver combo is great!
recommended crossover of tweeter is 5k
Well, there are various recommended frequencies. One being 3.5k but from talking to various people experienced with slot tweeters, and other so-called super tweeters, (which is only in the PA sense because they really don't even make it to 20k) they recommend crossing over pretty high- like 5k.
Which is worse, a tweeter straining to go low or a whizzer cone woofer trying to go high? In this case I made my choice, seems a tweeter under stress would be the more harsh and annoying possibility... I also considered the Eminence Beta without the whizzer with a horn driver and waveguide but the costs started to mount up, and this is supposed to be a fun speaker that high school people can afford to build ( especially if they stumble on some plywood! )
Well, there are various recommended frequencies. One being 3.5k but from talking to various people experienced with slot tweeters, and other so-called super tweeters, (which is only in the PA sense because they really don't even make it to 20k) they recommend crossing over pretty high- like 5k.
Which is worse, a tweeter straining to go low or a whizzer cone woofer trying to go high? In this case I made my choice, seems a tweeter under stress would be the more harsh and annoying possibility... I also considered the Eminence Beta without the whizzer with a horn driver and waveguide but the costs started to mount up, and this is supposed to be a fun speaker that high school people can afford to build ( especially if they stumble on some plywood! )
Re: I'd lose the whizzer
Of course you may, if you'd like i have pictures of other BIB's we've built including the 6" and 8"
this project has made me all giddy, now i want to do a larger pair
(bigger is better, right?)
the new source and amp sound much better for those of you wondering, originally it was an ipod and an old McIntosh amp
Godzilla said:
Of course you may, if you'd like i have pictures of other BIB's we've built including the 6" and 8"
this project has made me all giddy, now i want to do a larger pair
(bigger is better, right?)
the new source and amp sound much better for those of you wondering, originally it was an ipod and an old McIntosh amp
Very Cool! Those should really rock when you get them in the corners.
What did the x-over values end up at?
What did the x-over values end up at?
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