re: two woofers - maybe like this
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Freddi, I looked at the K's a few years ago, but never did come up with a suitable 15" driver...
Since I've acquired a number of vintage 12" Co- and Tri-Axial drivers.
Any experience with these worth mentioning?
I've got University, EV, Coral, Pioneer, still looking for a deal on some Jensen's, or some more EV's or one of the private labels built by Jensen....
Curious minds want to know....
John
Since I've acquired a number of vintage 12" Co- and Tri-Axial drivers.
Any experience with these worth mentioning?
I've got University, EV, Coral, Pioneer, still looking for a deal on some Jensen's, or some more EV's or one of the private labels built by Jensen....
Curious minds want to know....
John
The original big Karlson, the Ultra Fidelity K15, is IME the most forgiving. As they get smaller, they seem to get trickier. Prepare to do some tweaking and experimenting. OTOH, there have been some promising new experiments with smaller Karlson type boxes recently.
In general drivers with low Qts and low Fs have the best chance of success.
12" in a K15 can sound quite good. Is one of those vintage EV coaxial a 12TRX-B? This combination shouldn't work, but it does.
I didn't like my K15 for guitar, but it is very good for bass.
This old design does some things very well, and while it has its flaws, as do other vintage designs, it's worth a try.
In general drivers with low Qts and low Fs have the best chance of success.
12" in a K15 can sound quite good. Is one of those vintage EV coaxial a 12TRX-B? This combination shouldn't work, but it does.
I didn't like my K15 for guitar, but it is very good for bass.
This old design does some things very well, and while it has its flaws, as do other vintage designs, it's worth a try.
those may be ok - things like Diffusicone 12 are good sounding in the midrange in K12. Here's something which had fs over 100Hz and fs >1 (suspension must be dried out) - put it in K12 for a joke - it sounded very good
University UCX122 12"
University UCX122 12"
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IIRC it was in the subwoofer forum that a guy built some rough K's and stuck 4 small woofer in it, 2x2 config, maybe a year ago.
IG
I prefer the idea of sticking to one bass driver as well. Seems like Karlson must have been happy with the K15 design, as it stayed pretty much the same, maybe except for a port board modification at some point (?). K12 went through many iterations and he might not have been "done" with that one. In between, X15 also saw some changes AFAIK.
If you search for "Fostex FF225WK" or "FF225WK" in Google, my YouTube of this very driver in the small SK8 comes up first page.
Karlson SK8 with Fostex FF225WK - YouTube
IG
I built the 1955RE version of K15.
First with Eminence DeltaPro 12A, and this performed excellently.
But it was "obvious?" this cabinet deserved something bigger, or
so I told myself...
Then "upgraded" perhaps too far with SigmaPro18A2. This barely
fits with some removal of material in the bottom and shelf. Goes
much lower now, but no hit in the chest, and the walls are not
exactly shaking anymore. Magic smoke almost completely gone.
Does not impress.
I would assume 15 works as the original intent, I've never tried.
12 works, But 18 is wasted in K15 enclosure of my experience.
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IIRC freddy had some amount of success with an 18", I don't know which, in K15. Better stick with nominal driver size if possible though, or even go smaller if motor is a bit weaker.
IG
I don't know if an 18" cabinet need scale to K18 width,
the 1955RE cabinet already seems plenty wide enough.
But it would certainly benefit both 18" fit and function
if it were a bit taller inside.
Could go about a foot taller and still get it into the back
seat of my car, but any wider or deeper isn't an option.
the 1955RE cabinet already seems plenty wide enough.
But it would certainly benefit both 18" fit and function
if it were a bit taller inside.
Could go about a foot taller and still get it into the back
seat of my car, but any wider or deeper isn't an option.
fwiw I liked 18" "ok" in Karlson - my first driver was an Eminence with lower mass (103g mms) and lower qts than the Sigma. 18's in the 130 gram region were more mellow and lost some midrange. One thing I remember is the improved subjective quality in the mids when moving a 130 gram 18" Eminence from a bass reflex to a Karlson. For whatever reasons the indirect radiator sounded much better than the cardboardy tone of the same driver in a 6 cubic foot quasi RJ vented reflex (there was no substantial blocking of the driver but the box had RJ dual vents. An EVM18B with only 80 grams moving mass works well in a taller K18.
22"x16"x~42"
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22"x16"x~42"
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here's a driver I have to revisit - although not fullrange, Beyma's 12cx was more extended than Eminence's older 10&12cx - its sat in this K12 for 6 years but not been run yet - qts is higher than spec but its extension is an important element not seen in simple T-S data. That is a factory Karlson 12.
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This would likely be my next K18 (if I ever get around to it...)
All about loading for bass, strengthening the back and wings.
Little attempt to optimize upper chamber's high order modes.
I got a much different design for that sort of thing...
All about loading for bass, strengthening the back and wings.
Little attempt to optimize upper chamber's high order modes.
I got a much different design for that sort of thing...
Attachments
nice collection. here's mine
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