Karlsonator 12 for 12LTA

so far I've only run the Karlsonator 12 with the old Nirvana stamped frame Super10 - which was very "fast" sounding - the Karlsonator 12 works very well with Beta 12LTA augmented by a so-so Goldwood 1005 knockoff and I'll eventually load some of my coaxial including cast frame Eminence in several flavors, Beta10cx, Beyma 12cx and a P-Audio 12cx.

many thanks to Greg B. for the concept and plans and many thanks to TheJessMan for his superb realization.

my early impressions are very good for this Karlson variant - I recommend it.

The Build
https://www.facebook.com/media/set/?set=a.696242867088868.1073741850.601735219872967&type=1

dimensions - a larger plan is available at Greg B.'s album
Karlsonator.png


impedance plots obtained with a 50 ft run of 10 ga zip cord - just to show tuning

pyPVpGu.gif

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sorry for mess - gotta clean - I've a lot of chest pains. Note Earl's book holding
the wire for the piezo - lol

oekiaab.jpg


don't worry - there are plenty of screws for the wings- I popped the 12lta in the cabinet
for a short run but am pleased enough to let it be permanent.

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So you like the sound of the 12LTA then? The bass tuning freq (if assumed to be in between the two impedance peaks) is at 40 Hz which matches my sim. As I recall the 12LTA is not the best driver for the Karlsonator so expect improvement as you switch. I think the Beta 10CX or 12CX will be more balanced. Nice addition to your collection!
 
12lta sounds good for what it is and overall sounds very good in the new Karlsonator. 12lta's power response gives good vocals when a simple piezo tweeter is added- I'll load Beta10cx plus a compression driver in the other cabinet in a day or so for comparisons. Karlsonator 12 may be good for a number of fullrange drivers. Considering I paid $39.95 for the Eminence and $1.50 for the Goldwood, it really is a nice performer and the best overall I've heard from 12lta.
 
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it'll probably be a few days before I can load Beta10cx. I have a number of Eminence 12cx but not Beta - mine range in magnet slug weights from 54-80-109 ounces with the low moving mass 80oz magnet 12cx having the highest sensitivity.

12lta is normally not a favorite of mine but I think in the Karlsonator 12 that doing a better job than usual and that Karlsonator 12 may accommodate several fullrange and coaxial with good performance.

a dedicated Karlsonator10 for Beta10cx (or Nirvana) would be interesting if the result is a cabinet in-between Karlsonator 8 and Karlsonator 12 in size.

perhaps 12lta has fallen in favor as there seems little attention to this thread - or I didn't hype the title enough :D

here's my smallest motor Eminence 12cx with custom smooth cone and like the Beta series is "hornless" - ironically they were custom made for a former president of Cetec-Gauss who was there during the development of their 18" Karlson (that would have been easy if JEK's K18 plan were around)

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my TSG coax will be tried with several good compression drivers - it should handle 300 watt peaks well
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I let the Goldwood 1005 run full open -is Godzilla 2014 as much fun as 2000/Final Wars/Giant Monsters All Out Attack? - his head looks flattened and a bit too small - same for the teeth - I've got too much chest pain to go to a theater - if alive later on then will buy the blu ray.

to me, the new Zilla looks a bit like Dick The Brusier only not as tough
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Can't get much simpler than that. I think I can handle it. Haven't seen Final Wars but it's probably more fun. Godzilla is rather benevolent in the new one and I've never been a fan of that. Very un-monster like. Really sorry to hear about your chest pains. Keep us updated.
 
Hi K-Konstructeurs.
I like Godzilla, so I decided to ask if you think the following 12" Beyma driver would be appropriate for the K12 or Karlsonator 12. Any encouragement or discouragement is appreciated. I only need it for bass up to a couple/few hundred Hz for the moment, with later plans to move them to the workshop with some fullrange 10" Richard Allens.
Beyma 12g125
Sd = .051 m^2
Fs = 41
Vas = 122 litre
Sens = high 90s
Qms = 2.01
Qes = 0.31
Qts = 0.27
Xmax = 4mm
Bl = 16.8

I don't need Godzilla bass, just enough for normal acoustic music and the random Yamaha electro organ.

Many thanks!
 
I didn't run my usual kludged WinISD simulation, but on paper, I'd say the Beyma is ballpark for a Karlsonator 12.

Which Richard Allan drivers, CG10T's? I had a pair I used in Karlsonettes. That was decent enough, but they would have preferred something larger. The Karlsonator 12" is more likely to do good with them. If indeed the CG10T, you will need a helper-tweeter with the driver behind the K-slot, but you probably anticipate that if you've listened to them before.
 
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Joined 2012
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Hi K-Konstructeurs.
I like Godzilla, so I decided to ask if you think the following 12" Beyma driver would be appropriate for the K12 or Karlsonator 12. Any encouragement or discouragement is appreciated. I only need it for bass up to a couple/few hundred Hz for the moment, with later plans to move them to the workshop with some fullrange 10" Richard Allens.
Beyma 12g125
Sd = .051 m^2
Fs = 41
Vas = 122 litre
Sens = high 90s
Qms = 2.01
Qes = 0.31
Qts = 0.27
Xmax = 4mm
Bl = 16.8

I don't need Godzilla bass, just enough for normal acoustic music and the random Yamaha electro organ.

Many thanks!

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:
 

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Thanks a lot, esp. xrk for the simulation. Scaling the width shouldn't be a problem. IG, yes, those are CG10 RAs. Who knows if the Karlson will ever make it out of the lounge.

Richard Allan CG10T is a fine driver. Not much above 8kHz or so, but below, it's all quality. I would have liked to try a 80L sealed box for them. I did 50L vented, but that was a tad boomy in my small room. 120L+ would be more like it. The doped cambric accordion surround is pretty great and ages well. Fs on my pair was still low, perhaps more so than factory specs. Here's what I measured for my pair FWIW, hard to say if yours have aged the same:

Richard Allan CG10T

Re: 7.35 ohm
Fs: 38 Hz
Qms: 10.2
Qes: 0.48
Qts: 0.46
Vas: ~115 liters
BL: 8.25 N/A
SPL: 93.2dB/W/m