Goldwood's GW1858 does pretty well in an H-baffle - maybe a bit "fat" - works to ~32Hz - used to be about $65 - now ~$96 ...
That H-frame is insane !
Just considering the wall behind, how far from it should be positioned to get reinforcement of the backwave bouncing and returning... but already expanding and the lambda/2 law goes to hell 🙄
Scott G ( or L ) would be with me on this one 🙄😎
Just considering the wall behind, how far from it should be positioned to get reinforcement of the backwave bouncing and returning... but already expanding and the lambda/2 law goes to hell 🙄
Scott G ( or L ) would be with me on this one 🙄😎
OB ( open baffle or open back, or open whatever, see the Nola Thread ) for the mid-tweeter seems ok as the waves are relatively low in amplitude and short in lambda/2
The offset on the baffle helps to spread diffractions, well, er,reflections,well, er,radiation it is an integer...still lambda/2 regulates the space
The offset on the baffle helps to spread diffractions, well, er,reflections,well, er,radiation it is an integer...still lambda/2 regulates the space
Well, that pdf of MJK's open baffles with the goldwood 18 and 4" full range I could believe makes the full sound i'm looking for... Certainly he has the math and graphs to back it all up. That said, it looks like thats $540 just in drivers.. though i'm sure you could opt for one of the lower cost fostex drivers instead to bring the cost down somewhat. He's using dual amps and active crossovers as well, which are not in my current plans (or budget).
At the end of the day, I guess i still need to hear one of these open baffle setups to experience what kind of sound they have to really be sold on them, vs doing an enclosure of some kind.
Also WAF has not been mentioned yet, but theres probably a line there somewhere (though she was grudgingly accepting of the BBBIB).
Also worth mentioning is that i have 2 small children running around who will inevitably find jt interesting to poke at speaker cones, store toys in any ports or open areas, etc...
Does the OB woofer need to be on the floor to couple with it, or could it be put on a stand? This is where a sealed/ported/horn/tl/etc enclosure seems to have one more little advantage to OB... they look like furniture at least. 🙂
At the end of the day, I guess i still need to hear one of these open baffle setups to experience what kind of sound they have to really be sold on them, vs doing an enclosure of some kind.
Also WAF has not been mentioned yet, but theres probably a line there somewhere (though she was grudgingly accepting of the BBBIB).
Also worth mentioning is that i have 2 small children running around who will inevitably find jt interesting to poke at speaker cones, store toys in any ports or open areas, etc...
Does the OB woofer need to be on the floor to couple with it, or could it be put on a stand? This is where a sealed/ported/horn/tl/etc enclosure seems to have one more little advantage to OB... they look like furniture at least. 🙂
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Here is a smaller passive example using Eminence and Fostex. I have Jordan Eikona in OB with four 12" woofers in U frames. Yes, they need to be on the floor http://www.quarter-wave.com/OBs/OB_Design.pdf
FWIW, my fishers probably go down to 50 hz or so, and my cheesy little powered sub something like 33 hz, but is boomy and flabby sounding.
Just for clarity:
My intent is to make new mains that went plenty low for music, so say at least 40hz. For movies, I'd fire up a larger powered sub (yet to be built), probably something like a lilmike F20 or lilwrecker.
Just for clarity:
My intent is to make new mains that went plenty low for music, so say at least 40hz. For movies, I'd fire up a larger powered sub (yet to be built), probably something like a lilmike F20 or lilwrecker.
Scott, thats more reasonable, thanks. Though the low freq extension of that goldwood 18 is nice. 🙂
I guess the OB woofer is using the floor reflection for bass extension as well.
I guess the OB woofer is using the floor reflection for bass extension as well.
Even Linkwitz recommends a sealed sub below approx 40Hz. I'm experimenting with Infinite Baffle (not sealed box) for the bottom octave.
The floor effectively becomes part of the baffle, so, in a sense yes
The floor effectively becomes part of the baffle, so, in a sense yes
More stuff from Martin J King, this is second part of passive OB and comparisons of different frame types http://www.quarter-wave.com/OBs/OB_Design_Part_2.pdf
http://www.quarter-wave.com/OBs/U_and_H_Frames.pdf
http://www.quarter-wave.com/OBs/U_and_H_Frames.pdf
Grab the 12lta, some cheap ply and whip up a pair of Emkens.
They're great fun, very live sounding and I didn't really miss anything in the bass department at all 😀
Best of all it won't have cost you much to try
They're great fun, very live sounding and I didn't really miss anything in the bass department at all 😀
Best of all it won't have cost you much to try
Martin's website is certainly a flood of information! I'd been reading about transmission lines on there, not so much OB.
JRKO, didn't you build a few different enclosures with the 12lta? I was thinking it was you on one of the horn or tl 13lta threads... You liked the emken best? What else did you try?
JRKO, didn't you build a few different enclosures with the 12lta? I was thinking it was you on one of the horn or tl 13lta threads... You liked the emken best? What else did you try?
If it helps any, here was this mornings playlist...
Bach - Toccata
Nin - Reptile
Pentatonix - Bohemian Rhapsody (cover)
Pentatonix - Radioactive (cover)
Spinners - Rubberband Man
Sara K - Break my Heart
Rebecca Pigeon - grandmother
Bee Gees - Grease
Perturbator - Sentient
Somewhat eclectic.
Bach - Toccata
Nin - Reptile
Pentatonix - Bohemian Rhapsody (cover)
Pentatonix - Radioactive (cover)
Spinners - Rubberband Man
Sara K - Break my Heart
Rebecca Pigeon - grandmother
Bee Gees - Grease
Perturbator - Sentient
Somewhat eclectic.
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Zilla is your man for different 12lta enclosures I think.
First I used the 12lta in a big 3 way. It ran full range but had a 15 eminence on each side and a fostex super tweeter to add sparkle.
Then they went in the emken which I loved! They are just joyous when in the emken. Because the attack so well and the aperiodic design gives them what seems immediate start/stop dynamics. It's like jumping in a puddle when you're a kid - who cares about the measurements etc I'm enjoying myself too much to care!!! Check in with Sippy. He made them too. Oh and check the Emken thread for details about making a phase plug. The benefit is not subtle! Someone made measurements to prove it too - and yes the irony of quoting measurements is not lost on me 😉
Made me realise that all full rangers, even a 12in need a little help. Also made me realise I value midrange above all else and so I'm now building a 3 way with the 10in mids covering 150-1500hz 😀
First I used the 12lta in a big 3 way. It ran full range but had a 15 eminence on each side and a fostex super tweeter to add sparkle.
Then they went in the emken which I loved! They are just joyous when in the emken. Because the attack so well and the aperiodic design gives them what seems immediate start/stop dynamics. It's like jumping in a puddle when you're a kid - who cares about the measurements etc I'm enjoying myself too much to care!!! Check in with Sippy. He made them too. Oh and check the Emken thread for details about making a phase plug. The benefit is not subtle! Someone made measurements to prove it too - and yes the irony of quoting measurements is not lost on me 😉
Made me realise that all full rangers, even a 12in need a little help. Also made me realise I value midrange above all else and so I'm now building a 3 way with the 10in mids covering 150-1500hz 😀
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Gotcha, maybe Zilla will chime in. Here's that Emken thread
Ladies & Gentlemen - The Emken
Emken sounds like a contender, though i'm not looking forward to making beveled cuts of any kind haha. That's part of the draw of the BIB design. Concerned i will be underwhelmed by the bass response too... tight and fast is good, but sometimes there are some requirements for boom boom. Just not boomy on everything.
I'm still sort of surprised that no one is suggesting any of the horn or TL designs... is that stuff all old news and OB is the new cool thing to do?
Perhaps also worth mentioning is that I sort of started this adventure thinking of building a Klipsch khorn or jubilee clone... again, going for big full sound, with correspondingly large enclosures....
Ladies & Gentlemen - The Emken
Emken sounds like a contender, though i'm not looking forward to making beveled cuts of any kind haha. That's part of the draw of the BIB design. Concerned i will be underwhelmed by the bass response too... tight and fast is good, but sometimes there are some requirements for boom boom. Just not boomy on everything.
I'm still sort of surprised that no one is suggesting any of the horn or TL designs... is that stuff all old news and OB is the new cool thing to do?
Perhaps also worth mentioning is that I sort of started this adventure thinking of building a Klipsch khorn or jubilee clone... again, going for big full sound, with correspondingly large enclosures....
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If cutting the bevels scares you then the cuts required for th khorn and jubilee would send you into shock😀
For dynamics a line array is pretty awesome. And as they tend to use multiples of the same driver, they're technically are full range 😉
The JX92S is no longer available, and in my experience has a hard to listen to top end. The Mark Audio Alpair 10.3 is the direct size competion, in my experience better sounding (althou to get to its best needs lots of break-in), and it is currently on sale at Madisound ridiculously cheap (Markaudio Alpair-10 Gold 6" Full Range Gen 2 — silver drivers can also be had). It would be a very suitable substitute. I have a surplus pr of Goldwoods unused if you are interested. We built a version of the smaller MJK OB with FF85KeN and Eminence Alpha 15. It offered very good performance but there is something about the sound of all the OBs we have built that doesn’t quite sound right.
More pics here: Shutterfly
This used a passive XO. Going active gives a hugely greater amount of flexibility. Least expensive line level XO are Passive Line Level XOs (PLLXO). With one of the decent, but cheap Class D amps, one can spend less than the cost of the really big parts one needs for a passive XO this low. There are also some fairly frugal DSP XOs that also give you inobtrusive EQ.
dave
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