Karlson Slot loaded horn

[rjb]

A design posted on the Trading Post Forum has me interested. Its a back loaded horn with a Karlson slot on the mouth, Designed by RCA-Fan, but I think based on an original Foster design. Details are here;-http://gallery.audioasylum.com/cgi/...serImages=21168

There are a number of relevant pictures.

I presume these items are now sold, so it may be a good time to open up discussion on this design.

It seems to me that this may reduce some of the disadvantages of the normal BLH. but I'm a horn novice.

There has been previous discussion on mass-loading BLH's as well that may be relevant.

I'm contemplating making one to try, but using a coral driver, but have tried to model the original without sensible results, before attempting a model with the change in driver.

Any takers? Scott? Planet10?

 

[awhite1159]

Where's Freddy when you need him? Freddy, your slacking off.

Freddy is the resident K-slot expert. I have seen discusions of this enclosure on fullrangedriver.com as well. I am pretty sure it is the Fostex FE208E Sigma recommended enclosure with a K-slotted mouth.

 

[freddi]

I think RCA-Fan (Bill Woods) is at RMAF - theres good feedback for that design which has 5 internal pieces (Bill knew HF Olson and Voight) - I don't think the slot affected LF cutoff as thats a factor of bulk/flare/etc. It might sound "more open" - an A-B comparison would tell.

"real Karlson" (coupled-cavity) are fun - sometimes :^)

I'd like to hear RCA-Fans' horns - my cutter won't answer email, I've wasted $$ on unsatisfying FR waiting to hear from him - - where are they listed?

btw - got BK20 kit hope it goes together ~same bulk as K's little x15 - doubt if FR will be as clean when I hit it with 2 or 200W

 

[freddi]

Bill's BLH is modeled with a conical flare - the tapered slot was probably close in area to a regular rectangular opening. Ultrakaz and Fred 76 have built it.

AJ-horn simulation of K-slot with 4 drivers
http://img406.imageshack.us/img406/2440/kslot4drvrni1.gif

the horn would have a mouth which normally exits near the driver--see Fulmers article and patent

heres RAamond Bate's later little pipe with that type exit

http://home.planet.nl/~ulfman/images/bates1.jpg
http://home.planet.nl/~ulfman/images/bates2.jpg
http://home.planet.nl/~ulfman/images/bates3.jpg


for fun - Bill's tractrix in mid 1970's

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

41Hz K-slot and 30Hz "chimney" I believe the 30 Hz horn was rejected as not playing as well in the cello region as K-slot - RCA-Fan tends to put a bit of "hit" to get good cello sounds.

K-slot and chimney
http://img427.imageshack.us/img427/2581/chim70inbf8.jpg

Bill's K-slot horns topped by smaller AH! horns
http://www.acoustichorn.com/images/PETER.jpg

for a squat aperture look at Metro's T15 -but theres a coupled cavity K-wedge here
http://img218.imageshack.us/img218/5307/ksub1ju9.gif

 

[atmasphere]

I read about the Karlson enclosure a very long time ago. Amazing bass response was the hook. I get the feeling though that the actual bass response is not really as good as was written up so long ago. Isn't it the case that the Karlson was/is an example of speaker evolution from a time before things were sorted out? Or does it actually do something unique for its size and shape?

 

[freddi]

"real" K have excellent cone control.

8 cubic foot coupler with an 18" - front shelf not in this coupler so a reflective dip - lets see some 2-tone sine on FR in reflex and blh

small signal 34Hz sine below basspand K vs commercial front load horn
http://img281.imageshack.us/img281/469/34hz3rd6xv.jpg

20vrms 50Hz HD K vs front load horn horn
http://img54.imageshack.us/img54/4400/k18f20vrmsug3.jpg

2-tone modulation sine Beta 15CX swapped from a 50Hz tuned reflex the size of K15's rear chamber vs K15
http://img237.imageshack.us/img237/7187/dop1id9.jpg