Karlsonator

you guys are awesome!!!!

hi - Freddy "here", I'd think that would work in a traditional Karlson K12 with a half space rolloff corner around 75Hz and work well in GregB's Karlsonator12 with usable output to 40Hz.

the speakers designation is outdoor use.
i come to this thread, because i read somewhere that the karlsonators have a 'long throw'.

i struggle more with the high freq output than with bass.
if these do play 50hz (60 is ok, 50 better) at the low end and high enough to hook them up with a piezo horn, it would be....THE SOLUTION
 
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you guys are awesome!!!!



the speakers designation is outdoor use.
i come to this thread, because i read somewhere that the karlsonators have a 'long throw'.

i struggle more with the high freq output than with bass.
if these do play 50hz (60 is ok, 50 better) at the low end and high enough to hook them up with a piezo horn, it would be....THE SOLUTION

Makea sure you check out the mod suggested by Brian Steele regarding the GRS piezo horns. Looks like a winner for not much money.
http://www.diyaudio.com/forums/subwoofers/259509-new-sub-design-constricted-transflex-simple-build-series-tuned-6th-order-101.html#post4206681

The Karlsonator has a big sound that doesn't need baffle step correction. The speaker with "long throw" is the K15 fitted with an appropriate high sensitivity low Qts pro audio driver like a 12 or 15in Definimax. It will send 100dB with barely any cone motion. Read the "Speaker that Kicks Butt" thread. Karlsonator is not as efficient as it doesn't control cone motion quite as well. If you want a K15 style throw but with a smaller driver and still reach 60Hz you need to go with the XKi. It has good cone control for higher efficiency and ability to reach higher SPL.

I
 
Quantum Electrodynamics QED?

You will be glad you learned it later. I actually use a lot of what I learned in grad school (not QED!) to design and build speakers. :)

My last exam will be in theoretical physics in the end of may.
But i´m still two math exams away from that.
Now it´s hyperbolic geometrics and numerical calculus (which were the easiest available disciplines.)
 
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Sim of Buehgemeiste's driver in Karlsonator

Greg, indulge me, i copy the These tsp in hopes for a Fit into a K12.

Impedance (Z) 8 Ω
Resonant frequency (fs) 53 Hz
Max. frequency range f3-4,000 Hz
Music power 400 WMAX
Power rating (P) 200 WRMS
SPL (1 W/m) 99 dB
Suspension compl. (Cms) 0.2 mm/N
Moving mass (Mms) 44 g
Mech. Q factor (Qms) 11.39
Electr. Q factor (Qes) 0.52
Total Q factor (Qts) 0.50
Equivalent volume (Vas) 77 l
DC resistance (Re) 5.4 Ω
Force factor (BxL) 12 Tm
Voice coil induct. (Le) 0.9 mH
Voice coil diameter 65 mm
Voice coil former Kapton
Linear excursion (XMAX) ±4 mm
Eff. cone area (Sd) 530 cm2
Magnet weight 1.4 kg
Weight 4.4 kg

This driver has a very large Vas, consequently, you need a specially modified Karlsonator 12 for it to work properly. Basically take the design and scale the depth by 1.5x. It will a deep speaker at about 23in deep, width and height leave scale alone at 1.0x per plans from GregB.

Here is SPL at 2.83v and 1m:

463259d1422968693-karlsonator-karlsonator-1.5xd-bugh-freq-1m.png


Here is cone displacement with 39Hz 24dB/oct high pass filter and 16 volts:

463260d1422968693-karlsonator-karlsonator-1.5xd-bugh-displ-xmax.png


Here is corresponding max SPL:

463261d1422968693-karlsonator-karlsonator-1.5xd-bugh-max-spl-16v.png


You can see that the cone motion is not well controlled and hence max SPL is limited to about 110 to 112dB. Also, the HF fall-off may not be high enough for you to XO with a piezo horn tweeter - as they are typically above 2kHz.
 

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thanks, xrk.
doing that for me was an incredibly nice act.
the result is obviously not what i´m looking for.
maybe i should focus on creating more of a 'traditional pa-top'.
but i will no longer pollute this thread with those ideas.

edit:
please give me some hints what tsp to watch out for for karlsonators.
 
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money is the problem!

i´ll go for the K8 with my BG20s as a next project.
I have some cheapo piezo horns which i will try to couple with those.
this might be a quite satisfying solution for carrying too much stuff around.
i´ll look more into the monacor 8" (33€ per driver is to good to not check it out) and try to find a compact solution to let them play from ~120hz - 3kHz.
beneath that my friends cubo12´s will play, above of them maybe decent quality piezos.
i´m not awaiting wonders from such a setup....but you know it´s fun in the summertime.
 
edit:
please give me some hints what tsp to watch out for for karlsonators.

Part of the original reason for the (full size) Karlsonator was to make something that worked well with typical modern spec pro mid/bass drivers with BR type specs (moderate Qts & Fs).. The original Karlson K15 and K12 really 'like' the kind of Fs 25 qts=.19 drivers that barely exist anymore.


Anyhow, IIRC I used the Eminence Delta12 and Kappa12 for the initial modeling guesswork. Higher Qts drivers within reason should be OK also, with a little extra damping material. To a degree, it is oddly tolerant of different driver specs.
 
Xrk971,

thank you! I assume this is the link to Karsonator you're referring to.

questions: What causes the freq response squiggle around 150hz? Is there a way to flatten it and is a problem?
Does the karlson opening of the front chamber work as a hybrid of horn and ported box?

I will probably go with original plan and not make taller/narrower box unless it will help to remove that squiggle around 150hz.

regards,
Herman
 
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Xrk971,

thank you! I assume this is the link to Karsonator you're referring to.

questions: What causes the freq response squiggle around 150hz? Is there a way to flatten it and is a problem?
Does the karlson opening of the front chamber work as a hybrid of horn and ported box?

I will probably go with original plan and not make taller/narrower box unless it will help to remove that squiggle around 150hz.

regards,
Herman

Yes, that is the correct plan. The "W" dip is not always as bad in reality as the prediction. Keep in mind that the prediction is based on a 1-dimensional model and in real life, there is a 3d effect at the aperture and its interaction with the front chamber and driver. Usually, adding a layer of felt on on the inside of the K-aperture (facing the driver) helps reduce this W dip. Making the K-aperture terminate with a cusp rather than a slot seems to help too.
 
Yeah, the stub should be filled as shown, just like a Voigt pipe. The following areas should be covered in carpet felt or equivalent: bottom, bottom half of the back, divider plate behind the driver, and one side behind the driver. Vary to taste. :D

A small amount of thin craft felt on the back side of the wings just in front of the driver can be helpful sometimes, depending on the driver and system synergy.

I didn't specify stuffing and damping recommendations in the drawings since I only ever expected knowledgeable tinkerers and DIY'ers to build it.
 
What is the source of the felt that is needed here? Is it wool felt?

acoustical felt type F-11 has the widest bandwidth and best absorption coefficient of all versions and is excellent for such applications. synthetic felt is not useful over any kind of bandwidth. use only wool acoustical felt if you want the widest most even absorption.
 
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Yes wool felt is best but expensive. Recycled denim carpet padding can work too. I also know that Mr Clean magic eraser pads are same as the best commercial BASF sound abatement melamine resin foam used for sound stages. Those would actually work best and are reasonably priced for the small section behind driver chamber.

http://en.m.wikipedia.org/wiki/Melamine_foam
 
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