Mini Karlsonator (0.53X) with Dual TC9FDs

(just typed a 15 minutes reply but somehow hit a wrong key and lost it)

I'd like a Karlsonator10 or a really great "K10" (K12 will work well with a lot of 10" woofers/speakers)

On the cheap, BG20 measured well enough in GregB's "Karlsonator8" build by TheJessMan ("Triticum Audio") and that cabinet was really more effective than putting the mediocre 8 into the much larger Karlsonator12.
(A modest helper tweeter could make some good improvement to BG20)

I had Beta10cx in both the Karlsonator12 and a little 0.62 scaled K15. With stock Eminence xover values, its just not good on resolving detail and sounded lackluster. Perhaps Mike Chua's "Osprey" crossover for Beta10cx would make things better.

Karlsonator12 as drawn by GregB tunes to ~37Hz and Karlsonator8 ~41Hz. A somewhat higher tuning might help with some drivers to get more "punch"

I had Nirvana's "Super10" in the Karlsonator12 and it did very well. All of my Nirvana's are out of spec. AN10 (ferrite) started that way - AN8's fs rose a half octave never settling back down to the mid 60's.

John Karlson's Karlson Twelve (commonly called "K12") was tuned small signal to around 63Hz. The first K12 appeared in 1955 and called the "Karlsonette" (as K8 had not yet been introduced). Around 1956, K12's upper port board was canted 10 degrees forwards and used a distributed slit vent - perhaps to better deal with higher Q speakers. When a slit port K12 is driven with sine wave in the vicinity of tuning, many strong harmonics are generated - this doesn't seem to be a problem and even playing a bass guitar through that cabinet will not seem "off" - perhaps a strong/mellow organ pedal or dance sine sweep would show) I called the overtones - distortion - Dr. Geddes said the proper term would be "modulated noise")

FWIW - I like a K12 with Eminence's Kappa12A better than my Peavey FH1 horns. The presentation is quite different between a little K-tube +12K vs a 3-way horn system with Altec 511 as mid-horn - but the little K seems punchier and more definite in attack. A good K-tube can be made from 1" plastic pipe with a half ellipse slot and overall length of 5.3". Also, in some instances with tube on top,
a baffle at the compression driver (or dome tweeter) exit plane could provide some useful reinforcement of the tweeter's low end range. (use felt on top of
the cabinet below the tube to reduce reflections)

I'd appreciate ideas on new Ks. With a regular K, an extra chamber could be added to the top of the front chamber to smooth response and add some effective volume.


In the graph below, Karlsonator12 didn't have a fill in its stub, so there were resonant dips. I'm not sure even if Jesse's Karlsonator8 had much stub damping (?)

K3obtHk.jpg


MMJ illustration - MMJ has a fudge sim for this arrangement in hornresp
Karflex_60hz_for_Freddis_Kappa12a.png
 
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It’s been a long, long, long time... but I finally finished one 0.53x dual 3fe25-16 mini-k. Hooked it up to my tripath class d with Bluetooth just for a quick shakedown. The sound is nicely detailed and balanced at first impression. Need to get the other put together then maybe mess with stuffing a bit. Here are a few pictures of the finished speaker.
 

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Thanks X! I should have also mentioned, the kids bedrooms are right above my "speaker lab" so I wasn't able to test the speaker with any kind of volume yet. Can't wait to put some Class A power through it and get the second one done. Thanks everyone again for the great research, design, and plans for these!
 
Hi all have been trolling thru the mini -k thread for info.
Found these semi plans many years ago Anyone seen/built them?.
Just having finished the woodwork on me 10" Tannoy project i have a bit of 1/4" ply left over so might give these a go but scale em up slightly to fit a 2" driver , this one looks promising Fountek FR59EXE 2" Neodymium Full-Range Driver, lowish Qt and lowish Xm.
Any thoughts, laughs or giggles ?
 

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I have built small scaled K15's before (not Karlsonator, which is a ML-TQWT), the K15 is a 6th to 8th order bandpass reflex with a K aperture output lens. The simulations show that there is not much bass below 100Hz - and the prototypes prove that. However, there is great cone-control so good for loud high SPL pro-audio applications. I have made 0.25x scale and 0.46x scale.

Putting a 2in fullrange driver in one will not get you much other than the wider dispersion of a K-aperture, but a 2in wide driver is pretty wide to start with.
 
I have built small scaled K15's before (not Karlsonator, which is a ML-TQWT), the K15 is a 6th to 8th order bandpass reflex with a K aperture output lens. The simulations show that there is not much bass below 100Hz - and the prototypes prove that. However, there is great cone-control so good for loud high SPL pro-audio applications. I have made 0.25x scale and 0.46x scale.

Putting a 2in fullrange driver in one will not get you much other than the wider dispersion of a K-aperture, but a 2in wide driver is pretty wide to start with.

Might have a bash at it anyway,only need good treble for the tv as already got a small sub and existing speakers are hopeless.thanks for the reply
 
Experimenting this weekend with my dual 3fe25 speaker. I was finding it thin sounding in my usual listening space and the highs boarding on shouty and harsh. Right now I have .8mH paralleled with 5.5ohms of resistors. Sounding much better. I think I’ll forgo any more experiments with the single speaker and get the other one finished.
 
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Had a chance to take a look yet?

Sorry it took so long, I had problems with my virtual machine on the new laptop and had to reinstall Win XP on it and Akabak.

This is an interesting driver that looks a lot like the Faital Pro 3FE22 Nd magnet driver - but they are not the same. It has a rather low Qts, so required a rather slim cabinet. You may have to adjust the length of the baffle board a bit to allow the drivers to fit.

The size ended up being very non-standard at 0.47x Height and Depth, and 0.37X Width. This is for dual drivers in parallel and to that, add a 0.8mH inductor in parallel with a 2ohm 10W resistor as a BSC.

You will get something like this:
attachment.php


LaVoce SN030.72 specs:
http://www.lavocespeakers.com/lavoc...400817_LAVOCE_FSN030.72_3in_FULLRANGE_A.a.pdf

If we stick the Faital Pro 3FE22-8 in the same box, it is actually smoother:
attachment.php


Faital Pro 3FE22 8ohm:
https://www.parts-express.com/pedocs/specs/294-1101-faitalpro-3fe22-8-specifications.pdf

If you have a choice and can get the 3FEE22, I would go with that as it has a flatter response.
 

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...This is an interesting driver that looks a lot like the Faital Pro 3FE22 Nd magnet driver - but they are not the same. It has a rather low Qts, so required a rather slim cabinet. You may have to adjust the length of the baffle board a bit to allow the drivers to fit....

The size ended up being very non-standard at 0.47x Height and Depth, and 0.37X Width. This is for dual drivers in parallel and to that, add a 0.8mH inductor in parallel with a 2ohm 10W resistor as a BSC.

...f you have a choice and can get the 3FEE22, I would go with that as it has a flatter response.


X how would you rate this tall-thin box against the 0.53 for dual 3FEE22s ?
 
Sorry it took so long, I had problems with my virtual machine on the new laptop and had to reinstall Win XP on it and Akabak.

This is an interesting driver that looks a lot like the Faital Pro 3FE22 Nd magnet driver - but they are not the same. It has a rather low Qts, so required a rather slim cabinet. You may have to adjust the length of the baffle board a bit to allow the drivers to fit.

The size ended up being very non-standard at 0.47x Height and Depth, and 0.37X Width. This is for dual drivers in parallel and to that, add a 0.8mH inductor in parallel with a 2ohm 10W resistor as a BSC.

You will get something like this:
733717d1549232391-mini-karlsonator-0-53x-dual-tc9fds-lavoce-sn030-72-0-47x0-36w-jpg


LaVoce SN030.72 specs:
http://www.lavocespeakers.com/lavoc...400817_LAVOCE_FSN030.72_3in_FULLRANGE_A.a.pdf

If we stick the Faital Pro 3FE22-8 in the same box, it is actually smoother:
733720d1549232779-mini-karlsonator-0-53x-dual-tc9fds-faital-3fe22-0-47x0-37w-jpg


Faital Pro 3FE22 8ohm:
https://www.parts-express.com/pedocs/specs/294-1101-faitalpro-3fe22-8-specifications.pdf

If you have a choice and can get the 3FEE22, I would go with that as it has a flatter response.

Thank you, I really appreciate the effort.

So the LaVoce driver is out. I am able to get the 3FE22 at the same price as the 3FE25 - so it makes sense to rather go for the Neo if there is no price difference.

Glad you pointed out the 3" neo needs a smaller enclosure as I was going to use the normal 0.53x enclosure for dual 3FE22's.

No need for a BSC if using dual 3FE22's on the 0.47x enclosure I take it - part of the perks of the Karlsonator isn't it?

Would anyone be able to assist me with plans for the 0.47x enclosure? I would like to build one from wood :D
 
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No need for a BSC if using dual 3FE22's on the 0.47x enclosure?

If your placement is near a back wall, probably not. Balance of bass vs detail is a very personal choice so maybe order the 0.8mH air core coil (they are not expensive) and some resistors 0.5ohm, 1ohm, 2ohm, etc. and test it outside cabinet by attaching between speaker and input terminal. See what works for you.
 
If your placement is near a back wall, probably not. Balance of bass vs detail is a very personal choice so maybe order the 0.8mH air core coil (they are not expensive) and some resistors 0.5ohm, 1ohm, 2ohm, etc. and test it outside cabinet by attaching between speaker and input terminal. See what works for you.

I have a MiniDSP so I will probably EQ with that instead of doing so passively.
Will be a bit easier for me - however a friend wants a set as well and would not have the luxury and convenience of a DSP so could be useful for his set. :D


EDIT: @xrk971 are you able to see how much power can be fed into the speaker before xmax is reached (I assume we would reach xmax before the 20W power handling rating on the 3fe22's). If possible, with an xover @ 60hz / 70hz, 24db.
 
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So the amp i have been using so far is a lepai TA2020, and i assume i get about 10 - 12w out of it. I assume i will need about 30w to give the speakers what they need, so i am now building a simple velleman k8060 amp to go with it. To not contaminate the thread i made a new thread here.

I will post new frequency response curves when i know they get the power they need.