Stuff BR Box FE126e?

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The hybrid or the BR? We were very dissatisfied with the performance of our build of the hybrid.

The little BR looks to be a non-starter (at least for me) ... sim below

With either of these you are going to be looking for bass support. Once you factor in bass support, you might as well use the FE126 sealed...



  • FE126-factoryBR-sim.gif
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I'm doing the BR recommended design, do I stuff with fill, line with insulation, or do nothing?

If you haven't already cut material for these enclosures, and unless really constrained by space, you might want to reconsider.

I built a pair of these several years ago (for previous FE126E), and as with several of Fostex's "recommended" designs, they were quite underwhelming to say the least. Two public domain designs that I know work very well are the Buschhorn MkI modified to fit larger driver, and the latest generation of Frugel-Horn.


we don't always finish each others ....
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I do have this sub available: Sony SA-WM250 100-Watt Active Subwoofer: Electronics

What sized sealed box, same?

I'm just looking for something quick and easy to make to see what FRers are all about. I will go deeper into a horn type build later with this or another pricier driver.

probably anywhere from 8-13 liters would be fine

if new, make sure the drivers have a thorough break-in before finalizing XO settings on the sub and any additional EQ / filtering on the wide-bands

and you don't necessarily need to get spendier than this driver to get musically satisfying results
This hybrid BR - horn box from Fostex looks quite interesting. Why did it underwhelm ? It seems strange for Fostex to screw up that badly. It's a novel design. I'm guessing that the BR resonance is designed to pick up where the horn runs out of bass extension in order to keep the size small ? or does the horn pick up where the BR leaves off ?

Dave, your new avatar is scary man !
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I'd have to disagree there.

According to winISD, the f3 of a Q=0.707 sealed box would be over 200Hz. -10dB at around 120Hz. Integration with a single subwoofer without localisation would be nigh impossible.

I don't recall saying anything about single subwoofers, or even subwoofers come to that. ;) I was refering to the type of alignment Dave outlined in post 8.

The 126 is not a driver particularly well suited to vented alignments short of a horn with reasonably high gain. Not if you want a reasonably undistorted dynamic BW at any rate. Ergo if a horn of that nature is not practicable for whatever reason, then IMO it's best employed in a trad. 2 way setup, with dedicated woofers per channel, crossed at whatever your desired frequency happens to be. 4th order slopes at 500Hz is one of my favourites to get a decent level of power-handling while only sacrificing a little at the bottom of the telephone BW (200Hz - 4KHz).
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Here's a thought.

The Frugel Horn Mk3 has come out, and Dave's looking for Beta testers. Construction looks fairly simple (curves might be a bit difficult to cut, but after that...).
Putting it in there would give enough extension to cross to a single subwoofer.
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