Mini Karlsonator (0.53X) with Dual TC9FDs

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It might be worth pointing out that the FH MkII is actually somewhat similar to the Karlsonator with regard to its general expansion. They are both offset positive taper TL with a final flared port section. The Karlsonator's final section has a less rapid expansion but uses a karlson slot, and is semi coaxial with the driver.

Obviously, the .4 scale karlsonator is much smaller. That in itself is a very large difference.

Thanks. I once heard some BLH and preferred the Karlson over that. But the FH Mk III and the Karlsonator are later developments and I was just trying to find out what the current opinion on difference is. I like the FF105WK metronome for near field listening and the HAK 6.5 for small gatherings. Although the latter will not destroy a dry wall (called gib board in our country) like some subs on HT, they go loud enough. In hindsight I should have made Freddy's HAK 8. If I was able to build anything today I would like to make a Karlsonator 8.
 
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In my homage to the FH Mk3 in foam core and scaled smaller for a Vifa TC9FD, I can say that it is a very nice sounding speaker, albeit no comparison to the real FH Mk3 can be made from this. But comparing my build to the Karlsonator 0.53x, the Karlsonator sounds much more full bodied with lots of mid bass and bass down to 60 Hz and it fills the room very well. The imaging of the Mk3 homage is better as it is narrower and a tall floor stander. The 0.4x has less bass than the Mk3 homage but the overall presentation of the two speakers is very different one being a rear mouth BLH and the other being a front mouth K aperture bandpass BLH. Overall I prefer the Karlsonators in either 0.4x or 0.53x scale. The 0.53x is substantially louder and can surprisingly fill quite a large space with nice sound as JScherrer pointed out in his build which is apparently used for music in a PA application. If I could only have one speaker (of the dozen that I have), it would be a Karlsonator as it works with all types of music very well and just sounds natural and easy to listen to for long periods without getting fatigue.
 
Here is an impedance sweep from my .4x Karlsonators, looks like they are tuned to about 100 Hz.
 

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Hi X,

Just so you don't think I have forgotten about the project, here is the current state of my 0.53X Karlsonator (w/ dual TC9FD) build. Things are so busy between home & theater that I only get a few pieces put together each week. Still probably weeks away from first sound, but they need to be up & running in the studio by mid-August.

One quick teaser: this will be my first build where I don't use veneer. Going with Tolex Vinyl from Parts Express (#260-7604 ).

Cheers, Jim
 

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Here is an impedance sweep from my .4x Karlsonators, looks like they are tuned to about 100 Hz.


You might want to play with the K-aperture slot tuning. My 0.4x FC seems to be tuned to 80 Hz, which matches the sims. The lossy FC panels probably absorb some of the energy hence the peaks are not as sharp.
 

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Hi X,

Just so you don't think I have forgotten about the project, here is the current state of my 0.53X Karlsonator (w/ dual TC9FD) build. Things are so busy between home & theater that I only get a few pieces put together each week. Still probably weeks away from first sound, but they need to be up & running in the studio by mid-August.

One quick teaser: this will be my first build where I don't use veneer. Going with Tolex Vinyl from Parts Express (#260-7604 ).

Cheers, Jim

Nice work! You can never have too many clamps. :D
 
I've got a hankering for a "K10" - should it be old school? - or the Karlsonator 8 made two inches wider? or something else? this size seems about the bottom for real kick with the original scheme. A nearly 2/3 size of K15 ~21"x15"x13" was punchy but had a bit too much peaking at ~210Hz IIRC compared to lower Fs. A scaled K15 might work. A higher aspect could too.
- be good to hit nearly 120dB without too much strain.
 
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Freddi,
A K15 scaled down to fit an 8 in PA coaxial driver (with Qts of circa 0.30 and efficiency circa 96 dB) can hit 119 dB max but only reach down to about 100 Hz. That is just the nature of the Karlson 6th order band-pass. Great efficiency and coupling between the cone and the air column but the low end goes higher and higher as you scale it smaller. However, it would be fine with a sub woofer.
 
from my limited experience, an 8 won't quite cut it - unless the back chamber were smaller

here's some rough in-room comparisons of a K10 size coupler with Delta10A vs K12 and X15 size couplers with strong 12" and 15". Enclosure and mic positions were fixed. I think at this perspective, there's a room null in the 200 region making cavity peaking look mild - perhaps it works to advantage.

a somewhat taller K10 might peak less in the 200Hz region?? - if so, does it have any other advantage? Is there a cavity profile better than another? Does the Karlsonator tend to avoid the peaking due to higher aspect and its large vent at the top of the front chamber?

Delta 10A has a big peak before rolloff and obnoxious resonance on pink noise when out of cabinet -a good crossover as in some Econowave should work. A K-tube should be used in preference to horn with 2-way Ks.

An externally hosted image should be here but it was not working when we last tested it.


a small 15" bandpass subwoofer with a lot of juice might be enough to go with some K10 size to augment bass to the mid 20s (?)
https://www.facebook.com/media/set/?set=a.717615628284925.1073741853.601735219872967&type=3

An externally hosted image should be here but it was not working when we last tested it.


K10 size with Delta 10A vs K12 with Pyle-Eminence PYM1298 (like Kappa12A)
6zjvfDb.gif


K10/Delta 10A vs Acoustic Control 115BK with EV 15L
D24Db8s.gif


K10/Delta 10A vs Karlson X15 with Peavey SC15
OMtKPYn.gif


K10 Delta 10A vs new-weak B102
qZJoDxK.gif
 
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One quick teaser: this will be my first build where I don't use veneer. Going with Tolex Vinyl from Parts Express (#260-7604 ).

Really, the western stuff? :D That should be fun. Tolex is actually quite helpful in quieting cabinet panels.

Hope you enjoy those.

BTW, I found that felt in the front chamber was useful for clearing up the treble with my mini karlsonators.
 
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Hi Greg B,

Yes indeed! Why go for plain colors when there is the stuff that looks like tooled leather? These will be monitors for our theater studio, so they are likely to get beaten-up. I am guessing that the Tolex vinyl will look better for longer than veneer.

Cheers, Jim

I used plain upholstery cloth, some micro suede they call it here, and used a water based contact glue. Worked like a charm - have in the past posted some pictures of my FF105WK metronomes in blue/black/jarrah combination.
 
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hey X - is the stock Karlsonator8 a good match for an Alpair 12p?


Freddi,
Yes, the K'ntor 8 can work well with the A12.3P. It will be limited in max SPL though as cone motion is not well-controlled.

Here is SPL vs Freq at 2.83v, Cone displacement at 12v (xmax with HPF), and corresponding max SPL (with -24dB/oct BW high pass filter at 38 Hz).

There is pretty good bass extension though. Do you have this driver on hand?
 

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My sim of the A12.2P (I meant A12.2P not A12.3p as shown above) in a 35.5 in tall MLTL that is 9 in wide x 10 in deep with a 2.53 in tall x 9 in wide x 0.719 in long vent at the bottom appears to show 60 Hz (-3dB) bass extension and 110 dB max SPL at 18 volts. You need a 24dB/oct HPF at 52 Hz to keep the cone from flying out of the basket though. So it would appear a MLTL provides better acoustic coupling but the bass is not as deep.