Karlsonator 12 for 12LTA

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This driver can work well in a 12 in Karlsonator to get 90 dB efficient bass down to 50 Hz. The HF is so efficient though it will need heavy BSC to tame the rising response to give a balanced sound. Make the box according to the full scale Karlosnator 12 plans but scale the width by 0.9x to reduce the volume if possible - that should still leave enough room for the bezel to fit. Use a 20 ohm + a 1.8 mH inductor in parallel to reduce the HF's to match the 90 dB bass level.

Here is what you get:
I'm going ahead with the Karlsonator K12, but I'm hoping to get some thoughts on one last driver option, specifically, whether or not it will work better than the Beyma 12g125 previously queried. The driver listed below is twice as expensive, so if it isn't an obvious improvement, it probably isn't worth it to me.

Many thanks again!

another 12"
Fs 35 Hz
Re 6.2 Ohms
Qms 11.17
Qes 0.229
Qts 0.225
Vas 160 Litre
Cms 383 um/N
Rms 1 kg/s
Sd 0.053 m^2
Xmax 4.5 mm
Vd 220 cm^3
Le 0.8 mH
 
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Joined 2012
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Astrojet,
The 12 inch driver you show above seems to work in a full size 1.0x scale Karlsoanator 12 cabinet. You may need some BSC as the HF efficiency seems about 5 dB higher than the bass output that can be generated.
X
 

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Can't believe you got no problems with cats or Giant Size Gozira
sharpening claws on your cones. Animules would be livin' in my
K if I din't put up serious screen. Looking at PE's 8" buyouts from
Community with an FS around 40 and surprisingly low Q. There
just has to be a way to put a whizzer on that...
 
it would be interesting to see how a PR does in whichever K model (K15 vs Karlsonator) is easiest for XRK971 to modify. Carl Neuser and his kid have apparently used PR in K's for over 20 years. (They don't share info as figure folks can do their own research.)

Wayne N's 10" passive radiator Karlson subwoofer helping eight 10" Scanspeak woofers in aperiodic vent enclosures.
An externally hosted image should be here but it was not working when we last tested it.
 
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it seems i've just received a pair of new beta 12cx's and PSD2013's (taking a chance on this PSD2002 replacement...).

I notice the specs of the current 12cx are very close to the 12lta (and 12cx was mentioned earlier in thread).

Anyone had a go with the current 12cx in the karlsonator yet? either in real life or sim?

I'm in a smallish room, but damn the torpedoes... was going to do open baffle, but I just got a new table saw and something more complicated would be nice to justify the purchase (i.e. any box speaker)
 
I don't believe I currently have a Beta 12cx but it should work well in Greg B's Karlsonator 12 using Eminence's values of 2mH/10uF for lowpass and 3.3uF/0.35mH for the highpass - battery bias could be tried for the highpass with two 6.8uF caps in series. I've not heard PSD 2013 but have tried those values with PRV D280ti, ASD1001S and the original APT50. Beta 12cx should also work in regular Karlson including K15, and I'd guess, 0.8 scale K15, but the Karlsonator will go deeper probably than K15.

A regular Karlson K12 seemed a bit too small to get a lot of impact from Beta12cx - but moving one into an X15 copy with ~ 2 cubic feet rear chamber , it perked up - I had a cd of a big Daiko being pounded, it played so loud that I thought the driver would be destroyed - but cone movement stayed within 1/8" peak to peak.

A regular Karlson 12 will work pretty well with Beta10cx.

out in front, that's a Beta10cx on an adapter ring in an old diy Karlson 12
An externally hosted image should be here but it was not working when we last tested it.
 
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freddi, thanks for the tips.

What about the small room bit? I must place them about 3ft from the back wall, and listening distance is about 6ft. side wall is about 2ft away on one side, and there is a drum kit on the left.

i worry because the diyaudio renaissance of the karlson was indeed title "speaker that kicks but in large spaces" ....

I suppose I will at least need to elevate them a bit since I'm so close?
 
Founder of XSA-Labs
Joined 2012
Paid Member
it seems i've just received a pair of new beta 12cx's and PSD2013's (taking a chance on this PSD2002 replacement...).

I notice the specs of the current 12cx are very close to the 12lta (and 12cx was mentioned earlier in thread).

Anyone had a go with the current 12cx in the karlsonator yet? either in real life or sim?

I'm in a smallish room, but damn the torpedoes... was going to do open baffle, but I just got a new table saw and something more complicated would be nice to justify the purchase (i.e. any box speaker)

Beta coax's from size 8 to 12 sim quite well in a Karlsonator. I know I have done them before and must be posted in one of the threads.
 
it seems i've just received a pair of new beta 12cx's and PSD2013's (taking a chance on this PSD2002 replacement...).

I notice the specs of the current 12cx are very close to the 12lta (and 12cx was mentioned earlier in thread).

The 12cx and 12LT sound pretty much the same to me, and IIRC the specs are close as well. 12cx should be good in a Karlsonator. You'd be the first.

FWIW, the 12LT was a little flabby sounding in the (smaller) K12, though it measured OK and didn't sound awful or anything. Frankly it sounds flabby in most boxes to my ears. :eek: It pepped up almost miraculously in a big fat TQWT. This was in fact was the inspiration for the rear loading of the Karlsonator. Needed a bit of BSC in the TQWT, but it should work well straight wired when the mass and slot loading of the K-coupler is figured in.

Excessive room gain can be somewhat controlled by raising them on small stands, if needed. There is also playing with the internal lagging materials, as well as EQ. I wouldn't worry too much about this. Karlsonator is a different design than a true Karlson like the K12 and K15, and they will load the room differently.
 
hey X - - do you still have Akabak running for the Karlsonator? If so I'd like
to see what could be done for typical medium mass 15" speakers in K15 or less bulk.

I suspect a nearly cubical XKi would give the lowest cutoff for a given bulk

(sorry about not having T-S in Akabak form - gotta get up early to see a surgeon)
 

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