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01-21-2009, 07:13 AM
|  | http://greenboy.us/forum/ greenboy designs: fEARful, bassic, dually, crazy88 etc | | Join Date: Dec 2000 Location: remote mountain cabin Montana | | | fEarful™ 12/6 & 15/6 bass enclosure designs - FREE!
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This is gonna be major WHUMPazz in a compact package.
Just waiting for a few final specs before filling in the blanks. I've got 6 iterations charted and measured. This could actually slim down from 18" to as far to 17" and have phase coherence and near-identical low frequency reponse with the larger version. It stacks with the fEarful 15+6.
For standalone use or when using two of them it can be set either way. If building two, the baffle should be mirror-image for best dispersion.
Last edited by greenboy : 02-21-2009 at 08:29 AM.
Reason: updated content
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01-21-2009, 08:01 AM
| | Registered User | | Join Date: Nov 2006 Location: Boston, MA | | | You're killin' me, gb! Good thing I don't have money for materials right now.
Can you predict approximate frequency response from the cab? Are you putting a crossover in? | 
01-21-2009, 08:03 AM
|  | Registered User | | Join Date: Feb 2006 Location: Dallas | | | forgive my ignorace--do you build and sell these or only offer the design for other to self build?
i saw a reference to fEARful in another thread, and it's interesting
thanks!
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01-21-2009, 08:26 AM
| | Registered User | | Join Date: Dec 2004 Location: Germany, EU | | that's really cool of you to share these plans !!!
I'm going to try model the cab in WinISD to have a looksee what the response is like 
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01-21-2009, 08:43 AM
|  | http://greenboy.us/forum/ greenboy designs: fEARful, bassic, dually, crazy88 etc | | Join Date: Dec 2000 Location: remote mountain cabin Montana | | Quote:
Originally Posted by davio Can you predict approximate frequency response from the cab? Are you putting a crossover in? | Unlike almost any commercial bass cabs on the market, these are large enough and tuned correctly to give full "flat" presentation of a low B/A string's octave overtone, and above that, and actually do a low F# well. Not only that - they don't run out of excursion even driven with lots of low frequency content well beyond their thermal rating.
I bi-amp, and building a near-perfect passive crossover for these drivers involves more than just doing the correct math, but also doing lots of acoustic measurements. But some of the commercially available generic crossovers should do fine. Sure, they won't be driver-specific but compared to typical woofer/tweeter cabs they should sound magificient with the right choice for the drivers involved.
At some point I suppose I could plug actual values into a crossover calculator and do a little better but every time I start I end up with such a high component count trying to get near the perfection I already get with an asymmetric active crossover... ; } | 
01-21-2009, 08:47 AM
|  | OVNIFX EXAR pedals rep for North & Central America | | Join Date: Oct 2005 Location: PDX, OR | | That looks mighty cool! Quote:
Originally Posted by greenboy If building two, the baffle needs to be mirror-image for best dispersion. | Does this mean the cones would be mirror image, i.e. for one of them the 6 should be on the left? Or below instead of above the 12? | 
01-21-2009, 09:00 AM
|  | http://greenboy.us/forum/ greenboy designs: fEARful, bassic, dually, crazy88 etc | | Join Date: Dec 2000 Location: remote mountain cabin Montana | | Quote:
Originally Posted by bongomania Does this mean the cones would be mirror image, i.e. for one of them the 6 should be on the left? Or below instead of above the 12? | Any combination of two cabs, one needs the midrange cone on the left, the other on the right. Then you place the cab on the floor with the midrange cone at top, and the second cab on top of it, upside down. The two midrnage cones end up next to each other. | 
01-21-2009, 09:07 AM
|  | OVNIFX EXAR pedals rep for North & Central America | | Join Date: Oct 2005 Location: PDX, OR | | | Any cost/benefit to having the top cab's ports at its relative top or relative bottom? | 
01-21-2009, 09:08 AM
|  | http://greenboy.us/forum/ greenboy designs: fEARful, bassic, dually, crazy88 etc | | Join Date: Dec 2000 Location: remote mountain cabin Montana | | Quote:
Originally Posted by ()smoke() forgive my ignorace--do you build and sell these or only offer the design for other to self build? | The plans are free. It's up to you to figure out any dimensional changes needed for different types of joins (rabbet, dado, etc). Essential hardware choices shoould be discussed in this thread and any other hardware and finishing is left to builders' discretion.
I've also recommended that people check out some finish carpenters or fine cabinetry contractors in their area if they because of tools or experience don't wish to DIY. With the economy in the state it is right now I'm sure they would appreciate the work.
At some point I should design some simple passive crossovers, but actually I'd encourage others to participate : }
Last edited by greenboy : 02-16-2009 at 12:44 PM.
Reason: updated info
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01-21-2009, 09:08 AM
| | Registered User | | Join Date: Nov 2006 Location: Boston, MA | | Quote:
Originally Posted by greenboy Any combination of two cabs, one needs the midrange cone on the left, the other on the right. Then you place the cab on the floor with the midrange cone at top, and the second cab on top of it, upside down. The two midrnage cones end up next to each other. | Are you saying that optimally, the midranges should be right next to (on top of) eachother? Does the lateral ~12 inches between left and right mounted mids make that much of a difference when it's on a stage?
BTW, when do you start shipping?  | 
01-21-2009, 09:10 AM
|  | Registered User | | Join Date: Jan 2008 Location: Oklahoma City, OK | | | Hey gb,
Would a Beyma 605nd or 18 Sound 410nd work ok in place of the Emi. Alpha ? | 
01-21-2009, 09:11 AM
|  | http://greenboy.us/forum/ greenboy designs: fEARful, bassic, dually, crazy88 etc | | Join Date: Dec 2000 Location: remote mountain cabin Montana | | Quote:
Originally Posted by bongomania Any cost/benefit to having the top cab's ports at its relative top or relative bottom? | It's actually free bracing/rigidity benefit to use a shelf instead of tubes, and I've been lavish in frontal area so they don't chuff even when hit with lots of wattage and low frequency content. In fact, if you ever do hear chuffing it's time to add a cab - because they are set to chuff just before overexcursion. | 
01-21-2009, 09:12 AM
| | Registered User | | Join Date: Feb 2005 Location: Edinburgh & Dundee, Scotland | | I thought you would have ideally wanted the mid range driver in its own enclosure?
But im not as knowing in speaker things as you 
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01-21-2009, 09:15 AM
|  | http://greenboy.us/forum/ greenboy designs: fEARful, bassic, dually, crazy88 etc | | Join Date: Dec 2000 Location: remote mountain cabin Montana | | Quote:
Originally Posted by davio Does the lateral ~12 inches between left and right mounted mids make that much of a difference when it's on a stage? | Yeah, it messes up horizontal dispersion patterns, and forgoes any coupling advantages in the midrange. Quote:
BTW, when do you start shipping? | 12th of Nevtember ; } | 
01-21-2009, 09:18 AM
|  | OVNIFX EXAR pedals rep for North & Central America | | Join Date: Oct 2005 Location: PDX, OR | | Quote:
Originally Posted by greenboy It's actually free bracing/rigidity benefit to use a shelf instead of tubes, and I've been lavish in frontal area so they don't chuff even when hit with lots of wattage and low frequency content. In fact, if you ever do hear chuffing it's time to add a cab - because they are set to chuff just before overexcursion. | Err... that's nice but is there any cost/benefit to having the top cab's ports at the top versus the bottom?
You described first making two cabs with mirror-image baffles, then said take two identical cabs and flip the top one upside down. I'm trying to understand if one method would have better results than the other. | 
01-21-2009, 09:23 AM
|  | http://greenboy.us/forum/ greenboy designs: fEARful, bassic, dually, crazy88 etc | | Join Date: Dec 2000 Location: remote mountain cabin Montana | | Quote:
Originally Posted by DaLaklandGroove Hey gb,
Would a Beyma 605nd or 18 Sound 410nd work ok in place of the Emi. Alpha ? | Yes, in fact I consider especially the 18 Sound 6ND410 to be essential for the 3015LF version because there the Alpha-6A really can't keep up. In a 3012LF version, it would need to be padded back 4 to 6 db though. The Beyma 605Nd is a good choice too but not as flat as the 18 Sound and a little trickier to do a crossover for. Same with the B&C 6MDN44. | 
01-21-2009, 09:23 AM
| | Registered User Director - Barefaced Ltd | | Join Date: Jun 2001 Location: Brighton, UK | | | Very nice. As soon as I can get hold of a 3012LF over here I'll be making a similar cab available, though I'm going to use the same tall shallow format as The Compact, possibly even the same exact external dimensions to give the woofer plenty of breathing room. I think I'll stick with the 605Nd for the midrange but include a bypassable pad for when you're using a second woofer-only cab. Should be a fantastic standalone cab with much more bottom and max SPL than any 1x12" or 2x10". Won't be cheap but it will be great value!
Alex | 
01-21-2009, 09:26 AM
| | Registered User | | Join Date: Dec 2004 Location: Rochester, NY | | Nice work GB. I think it is great that you post plans like this. It really makes a good first time DIY possible form someone without much experience.
So... who's building the first one?
I'm looking into a 2x12"+6" version myself. The Vb and Fb I've calculated are pretty consistent with what you've got here. My biggest challenge is figuring out a crossover design for a 4ohm LF load and an 8ohm HF/Mid load. | 
01-21-2009, 09:34 AM
| | Registered User | | Join Date: Nov 2006 Location: Boston, MA | | | When will the 3012LF be available for retail? | 
01-21-2009, 09:40 AM
| | Registered User | | Join Date: Dec 2004 Location: Rochester, NY | | Quote:
Originally Posted by davio When will the 3012LF be available for retail? | Word is sometime in February; but you never know. | | Thread Tools | Search this Thread | | | |
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