So I had a half hour spare this arvo and did this to the inside of the Karlson slot. I simply ran the scalpel knife on a shallower angle from the outside of the slot, making the opening smoother. Turning it from a 90 degree angle to a 45 degree angle. Might not do much, but might also be an easy fix to that somewhat closed in sound?
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Nope, that didn't do it.
So next step is to open up the lower aspect of the slot slightly, as X advises.
I dont really have any problem with this issue because I like the speakers without the slot anyway; they image nicely like that, just not as wide.
And it's just there's even more bass with the slot in place. I will make up a new template, print it out in A3 size and then make the wider cut out on the foamboard I have left over.
Although thinking about it, Im probably better off just modding what I already have here, given it's a subtraction exercise.
So next step is to open up the lower aspect of the slot slightly, as X advises.
I dont really have any problem with this issue because I like the speakers without the slot anyway; they image nicely like that, just not as wide.
And it's just there's even more bass with the slot in place. I will make up a new template, print it out in A3 size and then make the wider cut out on the foamboard I have left over.
Although thinking about it, Im probably better off just modding what I already have here, given it's a subtraction exercise.
the upper portion of a K-aperture "can" have a lot of subjective impact. If too tight then mids can seem dull. In a dedicated design the aperture usually ~ subtends a driver's surround like my 1960's K8
Art Welter's dad's "K8" interpretation from the distributed slot K12 is a bit larger than a factory K8 more open aperture and very good sound
Art Welter's dad's "K8" interpretation from the distributed slot K12 is a bit larger than a factory K8 more open aperture and very good sound
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If you like the bass with the aperture then try just a square plate from top extending down maybe 5in to 7in. Make it 7in and trim away slowly if it still changes the treble too much. That will give the vent a little more bass and open the front of the aperture to the no aperture case. Easy enough to try with a rectangular piece of foam.
Thx for the suggestions. Clearly my aperture is too tight as it is; I need to go to the other extreme and then find a happy medium. I like what the slot does for imaging (over a wider area) and for bass so I'm keen to optimise both. Will try
1) a wider slot at the top
2) a wider slot at the bottom - the wings seem a bit wide to me and the driver too hooded
3) a rectangle with no slot that extends down 5" from the top
1) a wider slot at the top
2) a wider slot at the bottom - the wings seem a bit wide to me and the driver too hooded
3) a rectangle with no slot that extends down 5" from the top
widen it a bit in the blue area - start a little lower than my botched attempt try to keep the change so the curve still looks nice,
When the aperture is too tight with wood construction, there's bounced components in that upper part trapped leaving the sound congested - dunno about 10mm foam. Also with wood K's if one snaps their fingers in the upper half of the front chamber, a ricochet/ treble slap echo (for lack of a better term) can be heard. With Fane's 250, I heard no artifacts with a K12 and hard surfaces. In an X15 copy and AN10, there were some making me wonder that in some cases, a straight panel as with K12 and the Karlsonator family is a better choice for small cabinets
https://i.imgur.com/Clisa4Z.jpg
Here's a tall K18 with curved reflector, clone of one X15's K-tube and generic crossover - its powerful, effortless and adept.
Done right, an "X12" could be very nice and all that would need would be to make a standard 1 inch diameter K-tube with elliptical slot about 5.3" long plus another inch un-slotted length to fit though K12's port panel. I have a beat K12 with Kappa12a and K-tube on top which is more impressive in ways than my Klipschorn. One can immediately feel a weighty presence on a Rudy Rosa synth track when the melody line is dropped to lower strings. Do not discount the Karlson heritage cabinets as they can make good substitute for midbass horn. K's need more power than proper front loaded horn but given cheap power, can outperform them for a given bulk.
18 inch two way Karlson speaker playing soprano voice and harp - YouTube
Look at my little K18's aperture - this sounded very congested when the wings were swiveled on their wings to give a 5/8" starting gap. With they are in this picture with about a 1.25" gap, the sound changed from congested to very good sound, plus think the narrow slot in the driver area made the 18" speaker look like a smaller woofer.
Excellent sound w. a Smith horn on top
When the aperture is too tight with wood construction, there's bounced components in that upper part trapped leaving the sound congested - dunno about 10mm foam. Also with wood K's if one snaps their fingers in the upper half of the front chamber, a ricochet/ treble slap echo (for lack of a better term) can be heard. With Fane's 250, I heard no artifacts with a K12 and hard surfaces. In an X15 copy and AN10, there were some making me wonder that in some cases, a straight panel as with K12 and the Karlsonator family is a better choice for small cabinets
https://i.imgur.com/Clisa4Z.jpg
Here's a tall K18 with curved reflector, clone of one X15's K-tube and generic crossover - its powerful, effortless and adept.
Done right, an "X12" could be very nice and all that would need would be to make a standard 1 inch diameter K-tube with elliptical slot about 5.3" long plus another inch un-slotted length to fit though K12's port panel. I have a beat K12 with Kappa12a and K-tube on top which is more impressive in ways than my Klipschorn. One can immediately feel a weighty presence on a Rudy Rosa synth track when the melody line is dropped to lower strings. Do not discount the Karlson heritage cabinets as they can make good substitute for midbass horn. K's need more power than proper front loaded horn but given cheap power, can outperform them for a given bulk.
18 inch two way Karlson speaker playing soprano voice and harp - YouTube
Look at my little K18's aperture - this sounded very congested when the wings were swiveled on their wings to give a 5/8" starting gap. With they are in this picture with about a 1.25" gap, the sound changed from congested to very good sound, plus think the narrow slot in the driver area made the 18" speaker look like a smaller woofer.
Excellent sound w. a Smith horn on top
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I took the K slot off today and just quickly installed a 7-inch rectangular section and it sounds much more open, so will play around with widening the slot from top to bottom a wee bit, until we get the right mix. Certainly with the rectangular shape at the top, it is back to being how it was without the slot, open and forthcoming, only with more bass. With the K slot in place, as it is, I need much more volume to get the right degree of loudness. So it is closed in in more ways than just voice and mids.
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I sourced my 3fe25-16 from here:
Fullrange speaker FaitalPRO 3FE25, 16 ohm, 3 inch
Paid like 30$ CAD /.driver, shipping+ customs included.
Customs duties cost 33$cad for 144$ cad goods value, shipping around 36$ cad with DHL.
Ordered on the 1st of september 03:00 am, got them today the 3rd.
Fullrange speaker FaitalPRO 3FE25, 16 ohm, 3 inch
Paid like 30$ CAD /.driver, shipping+ customs included.
Customs duties cost 33$cad for 144$ cad goods value, shipping around 36$ cad with DHL.
Ordered on the 1st of september 03:00 am, got them today the 3rd.
The Karlson purists will giggle and tsk tsk over this mod but in my opinion this really OPENS UP (please excuse the Trump-ism) the sound emerging from these quite incredible little cheapie foamcore giant killers.
The driver sits in a plastic storm water expansion joint. They cost knicks from our local hardware store. It makes the driver physically vulnerable (so the dogs cannot go near them and they know that).
Also you cannot use a Karlson slot on these; just a piece of rectangular foamboard, though I'm going to play around with different sizes as well.
So Im back to where i used to be when using the cylinders, only these do soooo much better bass.
Even from the next room these sound way more open and revealing. That little W5 driver is absolutely wizard, providing you don't feel the need to listen to party level music all the time.
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And another image.
One other thing that continues to impress is the width of imaging, even without the Karlson slot.
Is this because the rear wave and front wave are emerging as one? No idea, but there's no head-in-a-vice
imaging here. It's impressive and as good in this regard as the waveguides that I have the FE32-8s in.
One other thing that continues to impress is the width of imaging, even without the Karlson slot.
Is this because the rear wave and front wave are emerging as one? No idea, but there's no head-in-a-vice
imaging here. It's impressive and as good in this regard as the waveguides that I have the FE32-8s in.
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Right, only the driver would still be poking out and vulnerable, yes?
Actually, I think I get what you mean now; create a kind of rhomboid shape for the driver so it sits proud of where it normally is, but keep the rest the same. Would the increase in rear chamber size have any adverse effect though? As it is the extra space in the plastic chamber makes no discernible change to bass output.
I'm hunting around now for info on whether my Dayton 10-inch RSS265HO-44s will work in a pair of Karlson enclosures, or maybe my RSS390HO alone. Hoping they do - it would be neat going Karlson the whole hog.
Actually, I think I get what you mean now; create a kind of rhomboid shape for the driver so it sits proud of where it normally is, but keep the rest the same. Would the increase in rear chamber size have any adverse effect though? As it is the extra space in the plastic chamber makes no discernible change to bass output.
I'm hunting around now for info on whether my Dayton 10-inch RSS265HO-44s will work in a pair of Karlson enclosures, or maybe my RSS390HO alone. Hoping they do - it would be neat going Karlson the whole hog.
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when Matthew Morgan J. did his Karlflex aperture investigation, the slot disappeared. PA310 can sound muddy in a K. With a passive lowpass, that could be offset by making the driver/filter pull more current.
Here's a 15 inch Karlflex built that way:
https://i.postimg.cc/HscnRWkN/Karlflex-15-K-Aperture-E-Lab15-subwoofer-Mattcalf.jpg
I had no trouble with K12 with Fane 12-250TC, Beyma 12cx, Kappa12, and 12LTA , C12CX - other than 12LTA lacking jump factpr. It needs another pound of magnet slug - maybe more. PA310 in K12 sounds like its under water.
My tall K18 is quite open and sounds very good IMO with tube inside the coupler. All my 18 inch speakers sounded better in the K's than running direct radiator. I wish there were still an 18 like the old EV18B as mms was around 70g.
https://i.imgur.com/K9jYSvK.jpg
An ad for Cetec-Gauss's K18 showed a faster opening aperture than what seen in production models so far.
https://i.imgur.com/EkHHgqL.jpg
Experiments with a small K18 and tight aperture around the driver sounded very good as long as there was some place for the stuff rattling around in the upper half of the front chamber to escape. Raising wings height resulted in no improvement. An afterthought smoothing stub was added which worked.
https://i.imgur.com/peimDSx.jpg
To build a K-ish subwoofer with your Dayton15, the back chamber will have to be tuned low, or sealed. I currently don't have Windows as it has crashed for the 3rd time this year.
Here's a 15 inch Karlflex built that way:
https://i.postimg.cc/HscnRWkN/Karlflex-15-K-Aperture-E-Lab15-subwoofer-Mattcalf.jpg
I had no trouble with K12 with Fane 12-250TC, Beyma 12cx, Kappa12, and 12LTA , C12CX - other than 12LTA lacking jump factpr. It needs another pound of magnet slug - maybe more. PA310 in K12 sounds like its under water.
My tall K18 is quite open and sounds very good IMO with tube inside the coupler. All my 18 inch speakers sounded better in the K's than running direct radiator. I wish there were still an 18 like the old EV18B as mms was around 70g.
https://i.imgur.com/K9jYSvK.jpg
An ad for Cetec-Gauss's K18 showed a faster opening aperture than what seen in production models so far.
https://i.imgur.com/EkHHgqL.jpg
Experiments with a small K18 and tight aperture around the driver sounded very good as long as there was some place for the stuff rattling around in the upper half of the front chamber to escape. Raising wings height resulted in no improvement. An afterthought smoothing stub was added which worked.
https://i.imgur.com/peimDSx.jpg
To build a K-ish subwoofer with your Dayton15, the back chamber will have to be tuned low, or sealed. I currently don't have Windows as it has crashed for the 3rd time this year.
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