"Karlsonology" (Karlson enclosures/technique) what's happenin' ?

[ion]

Nice thread Freddi! I've wondered about "them strangelooking boxes" from time to time but asking google hasn't been too fruitful.

I'm hoping that experienced k-builders can help us novices shed some light on this kind of enclosure. For example, if one would like to build one of these, what would be the first step? Is there any general rules or at least clues for ideal driverparameters?

Jon

 

[MaVo]

Fig 1 from 1955 reflective patent

An externally hosted image should be here but it was not working when we last tested it.

this thing looks like a midbass/midrange tapped horn with a really fancy opening. should be a pain to script in akabak because of the opening. one would have to use a LOT of different sized radiators and ducts.

do you experience cancellation notches in the frequency response due to the backwave adding out of phase with the front wave?

 

[GM]

this thing looks like a midbass/midrange tapped horn with a really fancy opening.

do you experience cancellation notches in the frequency response due to the backwave adding out of phase with the front wave?

Yes it does! I wasn't aware of this particular patent which matches the way I've described building them in various threads to get around designing the K15's complex 8th order BP alignment for a specific driver.

Yeah, no getting around it above the pipe's 3rd harmonic.

GM

 

[freddi]

hi MaVo

dips - I think two spaced ~ one octave apart may come from "bounce" and would depend on baffle angle, etc.
http://gainclone.com/Karlson/index.php?topic=100.0

re: port - it sometimes seems to "fill" the first dip area
http://gainclone.com/Karlson/index.php?topic=45.0

here's ~ ground plane of a 30 degree tilt baffle coupler without front shelf vs Yorkville USC1

An externally hosted image should be here but it was not working when we last tested it.

 

[MaVo]

hi MaVo

dips - I think two spaced ~ one octave apart...

If i understand Karlson speaker correct, and my understanding comes from the picture i quoted, the rear radiation is not captivated in a closed box, but can add with the front radiation of the driver.

Rear radiation has a physical offset, its sound will arrive later in time at the listener than the front radiation. At a frequency, where the delay is half a wavelength long, the waves will cancel each other, much like comb filtering and produce a notch. this notch will occur every octave above this base frequency. If the delay is about a quarter wavelength or less, the rear and front radiation add, making the driver seem to have doubled radiation area. This is the principle of a tapped horn and also applies to the Karlson, if i understand it correct. Only that the Karlson has an additional strange device in front of the driver (i think you call them wings) and the pathlength is much shorter, so the frequency of the addition and cancelation will be higher than in a TH.

It is probably more complicated, since you have numerous paths, as the front radiation could travel into the box, be reflected and come out again, but thats pretty much the same effect, just at other frequencies.

 

[freddi]

for what its worth an old attempt to see group delay indoors with a little coupler whose inside height is 26.5 inches -- - does the group delay plot look reasonable? I don't have a good grasp of ARTA

x15 2035H response up close in my kitchen
http://img42.imageshack.us/img42/8958/x152035hfr12ao.gif

attempt to see group delay
http://img42.imageshack.us/img42/9068/x152035hgd13gd.gif