Does anybody have any knowledge of this

[jamikl]

Saw this photo in the gallery on audio asylum. Does anybody in this forum know of it or heard it? Another photo shows it built in oak with full fabric cover on front. Looks very impressive.

[jamikl]

Appears to have been used with 8" fostex drivers.
jamikl

[edjosh23]

My understanding is that it is designed for the FE208ESigma

Josh

[PeteMcK]

look similar to the 'Bates Pipe',
see the article on this page:

http://home.planet.nl/~ulfman/

[Scottmoose]

It's RCAFans hybrid BLH with a Karlson coupler. Supposed to be very effective.

[jamikl]

I've spent a lot of time searching the net for this sort of thing because I think that this, and the BIBs, are closer to the ideas expressed in the original patent and wonder if he might have tried to extract too much in his own designs. The BIB is half WL not quarter WL but shouldn't that give more harmonics to even out the coupler more than just having the odd harmonics in the quarter WL pipes?


The design in the photo is really interesting and I would love to know how it performed. As noted above, it really does look good in oak!!!
jamikl

[phase_accurate]

Someone on this forum is using it and posted a picture during the last week IIRC. But maybe my memory is wrong.

Regards

Charles

[Scottmoose]

Originally posted by jamikl
I've spent a lot of time searching the net for this sort of thing because I think that this, and the BIBs, are closer to the ideas expressed in the original patent and wonder if he might have tried to extract too much in his own designs. The BIB is half WL not quarter WL but shouldn't that give more harmonics to even out the coupler more than just having the odd harmonics in the quarter WL pipes?

The design in the photo is really interesting and I would love to know how it performed. As noted above, it really does look good in oak!!!
jamikl

Right. The BIB is a pipe-horn not a TQWT, and being 1/2 wavelength tuned has both odd and even harmonics.

Reading Karlson's original patent[s] I have to say I agree with you that the application of the slot to a pipe seems to have been what he originally intended (rear or front-loaded), and the subsequent K series cabinets (whatever their individual merits) were rather different.

From this POW, there appear to have been very few, if any, genuine applications of the original idea in home audio, and still fewer measurements, which is a shame. The aforementioned hybid 'horn' (though it's no longer a horn at all) is probably as close as you're likely to get. Ditto Dave's iBIBk, which is basically a BIB for the FE127E, inverted, with the driver moved to the ~ideal position, and a small K-slot sliced in the back (or front) to provide some of the vent area (which would otherwise be shorted / mass-loaded by the narrow coupling between cabinet and floor) and reduce some ripple (hopefully). The initial build suggests there's potential well worth exploring here, so I gather.