Thanks, guys. I messed up one side of the Karlsonator because I failed to notice that I was going to run out of glue stick before I made it all around the edge. 😡
zman01 - I listen to mostly acoustic music. Bluegrass, folk, some old country.
zman01 - I listen to mostly acoustic music. Bluegrass, folk, some old country.
So is the reduced volume and sparkle a characteristic of the Karlsonator or something wrong with my ears, or I picked a bad driver/cabinet size match, or I over stuffed it, or?
Still, you would think that partially covering a speaker would cut some sound.
Still, you would think that partially covering a speaker would cut some sound.
The Karlsonator does indeed attenuate some midrange and treble vs an open face speaker - it has to when something is placed in the way. Some drivers have a response that is synergistic and it sounds great. The dual 3FE25-16 or dual TC9FD is like this. I know a single 3FE25 or TC9FD also works well but you have to be careful with the aperture and not too much stuffing. Melamine foam pads in the rear chamber for foam core is good. Stuffing only from close end of internal path to the driver. If wood cabinet, melamine foam on front chamber and layer of foam core on inside of aperture.
If you have an airleak, somewhere in the rear folded TL, the bass may suffer. It is like a leak on a fingerpad of a flute when trying to play low-C.
Please read this post for tips and tricks (although for 0.53x scale dual, many principles apply to smaller 0.40x as well):
https://www.diyaudio.com/forums/ful...onator-0-53x-dual-tc9fds-296.html#post5577990
The Cornu will sound like a much larger speaker as it has a huge back loaded horn that produces a lot of midbass that is aimed along the wall - and this tends to make the speaker sound very spatious. Cornu is also open face so treble and mids are unobstructed. However, the Cornu is not as good with imaging and stereo sound stage as it is on a wall and not away from a wall to allow the spatiality to develop in a 3d way.
If you have an airleak, somewhere in the rear folded TL, the bass may suffer. It is like a leak on a fingerpad of a flute when trying to play low-C.
Please read this post for tips and tricks (although for 0.53x scale dual, many principles apply to smaller 0.40x as well):
https://www.diyaudio.com/forums/ful...onator-0-53x-dual-tc9fds-296.html#post5577990
The Cornu will sound like a much larger speaker as it has a huge back loaded horn that produces a lot of midbass that is aimed along the wall - and this tends to make the speaker sound very spatious. Cornu is also open face so treble and mids are unobstructed. However, the Cornu is not as good with imaging and stereo sound stage as it is on a wall and not away from a wall to allow the spatiality to develop in a 3d way.
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Thanks for the info. It sounds like I was hearing what these two different cabinets were expected to produce.
I believe I have a good seal on the Karlsonator because the bass was the best part and holding the speaker I could feel it "pumping" in time with the bass.
One thing is for sure - without the ability to quickly and cheaply crank these out in foam core, I never would have tried this experiment.
Now I have to decide if I want to build a wood Karlsonator for a pair of Eminence 12 LTAs I have.
I believe I have a good seal on the Karlsonator because the bass was the best part and holding the speaker I could feel it "pumping" in time with the bass.
One thing is for sure - without the ability to quickly and cheaply crank these out in foam core, I never would have tried this experiment.
Now I have to decide if I want to build a wood Karlsonator for a pair of Eminence 12 LTAs I have.
Try making it out of XPS link foam for the 12LTA but with plywood aperture. The Karlsonator isn’t perfect for all drivers or genres of music.
Tacky Glue works well for foam core or XPS and has more working time than hot glue. For gap filling I used a caulk that came in a squeeze bottle (the label is long gone).
What's the BEST Glue for XPS FOAM? - YouTube
What's the BEST Glue for XPS FOAM? - YouTube
Construction adhesive like non VOC liquid nails. There is also specially made XPS adhesive. They come in large caulk gun tube dispensers. The bond takes a couple of days to fully cure. Do not use VOC (organic solvents melt the foam).
I cut a hole in the side of the Karlsonator cabinet and removed a bunch of foam. Then glued the plug back in place. It made a big difference. More volume and sparkle. I didn't have time for a side by side comparison to the Cornu, but my initial impression is that I had it over stuffed or used too dense of foam.
Great. Overstuffing is something that I have also done and fixed by cutting a window on the side of a foamcore box and resealed the cut with hot melt glue.
I did a comparison again between the Cornu and the Karlsonator with the reduced stuffing. Now I like the Karlsonator better. Lol. The Cornu had more bass, but seemed to sound a little hollow on male vocals. I put a little stuffing in the horn mouths and that improved it, so maybe I need to remove the driver and play with stuffing in it a little.
But given the cost and ease of build, that 0.4 Karlsonator is a gem.
But given the cost and ease of build, that 0.4 Karlsonator is a gem.
With the slot “lens” on the Karlsonator you are essentially giving up on-axis upper response up for a more attenuated wide dispersion pattern.
Or that is the theory at least.
So you might want to EQ the upper part of the spectrum to match.
Or that is the theory at least.
So you might want to EQ the upper part of the spectrum to match.