Karlson

Hi Mr B1

I don't believe there have been any builds of TB46's Karlflex.

Will there be an omni reflector for your top driver ?
 

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Will there be an omni reflector for your top driver ?
First time I've seen such an omni reflector - thank you for posting it. Right now I really like the sound of it just firing up. If I get close I can hear the character of the throat, but 2-3 meters away it's extremely natural and voices seem rocks solid suspended in air rather than coming from anywhere - even in a mono setup. I also have what is a 90% scale version of the EV HP940 horn flare but I'll consider other options, including all you put forward, if I can't get the voicing right. Judged on someone else who went this path said it was easier to integrate rather than the horn amplifying the 500-3Khz area even more than the driver by itself does. You probably had the same with your EV+k-tube?
 
Karlson's final "Acoustic Transducers" patent 3540544 said an elliptical reflector could improve evenness of response and dispersion.

There are FOUR Karlson X15 at Ebay with their 3-panel ellipse approximation and slotted pipe tweeter. https://www.ebay.com/itm/334448068543?hash=item4ddea887bf:g:k7YAAOSwdOdih~5r

X15 was introduced in the fall of 1965 and originally sported a mini - clam/klam tweeter with 3" cone speaker to augment their CTS 15 inch woofer.

Karlson expert Carl Neuser favors curved reflectors in his builds. I'm pretty sure his X15 would be to regular size (28x20x15) so the reflector can not be vastly different than JK's X15 and still fit. Can simple ray tracing determine what works well? My t41" tall K18 sounds great - I think its height could be reduced to 36".

Its too bad there's a lack of appreciation for the Karlson design as something like Akabak 3 an a lot of modeling might come of with some answers without physical prototype.
 
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Hello everybody.
i want to build a karlson box for 15 "loudspeaker and then make changes, tests and measurements.
how did you draw the curve of the front panel?
what data did you use to create the exponential curve? . are those in the attached image exact?
what software did you use? is it possible to use geogebra?
curva karlson.gif
 
Built thee rest first, then do the front panels in cardboard with the mesurements above and try.
To make it, draw horizontal lines every 1/2 inch for example and report the lenght of that line on your cardboard, join the end of each line and you get your curve, no need to be that ultra precise. This is DIY , don't forget.
 
From 9 - 12 nov was the ETF'22 (European Triode Festival); a serious audio-event with 100+ international participants.
Everybody brings in stuff as this is a 4 days event.
Noted people form all over Europe, UK, USA, Sweden, etc.
Last years Korea, Japan and Australia was also present. Maybe next year ?

This time it was in a castle and our room was fun.
I had the task to take care of the speakers (open baffle Supravox with von Langa field coil + Karlson tube for mid/high).
We hooked up a 833 amp to the lows and a GU4 for the mid/highs.
Fun !

The K-tubes performed great.
Next audio-session seems to be 4 february for a local/national audio-event.

Regards, Reinout
 

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Tripped-over the spreadsheet you made in 2001 in backups yesterday (ah, when bits still had some respect). Must've gotten it from James' board (?)
No doubt and in my early days of trying to correctly communicate my tech knowledge, so Freddi/folk's? found it too hard? to use and never got around to redoing it since at that time folk's just wanted a complete 3D cab drawing.
 
Hello everybody .
This is my first measurement and I may have made mistakes so please understand.
it is a karlson prototype made my way in cardboard, the measurements are those of the minikarlsonator, height 40cm, width 23cm.
the opening with the exponential curve is present but unlike the traditional slot, mine has one
curved surface so as to create a triangular chamber , moreover the reflex ports are placed at the lateral ends .
for comparison I measured two twin 4.5" speakers. in the graph, the red line belongs
to the loudspeaker placed on the flat side of a large cardboard box. the green line instead belongs to the loudspeaker of the prototype.
those who know how to interpret a graph can tell me if it contains something that may be of interest or if it's all to be thrown away.
 

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Good morning DIY-Audio,

at that ETF (see some posts above) the speakers (Supravox 285GMF in open baffle + von Langa compression driver with K-tube) was measured. This was an interesting waterfall-plot. Very very clean above 2K (the Bryston 10B active crossover was set at 2 K). The combination of that field coil driver + K-tube works very nice.
THAT nice that i asked Wolf von Langa (present at the ETF) to make me a bespoke fieldcoil unit for the bas/mid in order to support the already nice combo in the highs.
Let's see and hear what this will lead to.....

Regards,
Reinout
(waterfall was measured at 2,5 meters; you can see the room is far from being perfect....)
 

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I've been listening to music for a few hours and I'm surprised by the power that this little box manages to emanate, even at medium volume I feel the vibrations in my legs. But now I feel something strange, I have to check the speaker joints.
no comment on the graph ?
 

arivel - - I'd like to see what you are proposing - do you have a sketch and pictures of your cardboard experiment to post?


I used a two variable equation Basic routine for the slot. Karlson's K15 and K12 had radial arc slots. X15 opened up a bit faster in its upper half to allow for the K-tube.

My internet K-friend Carl (whom I've not heard from for years) would typically evaluate 4 sets of CNC-ed tapers.

The aperture opening at its top has some effect upon system tuning and subjectively can tune how the cabinet responds to transients.

Carls formulae

Rear chamber volume
vbr ~(vas*qts*fs)/fc

Rear chamber lowpass area
vbf ~0.5 vbr; slp ~0.2-0.4 sd

K15 by Carl's estimation

vf = 2.3 cu ft
vb = 4.0 cu ft
sb = 32 sq inches (originally 40.5 sq inches)
sf = 222 sq inches

The rear shelf creates a port area of 52.5 sq inches with the back of the cabinet.

The front shelf creates an area of 73.5 sq inches with the front panel.

Karlson's originals have frontal aspect of ~1.47 and could use radial arc tapers (~51 inches for K15, 42" for K12)

(((((((((((((((((((((((((((((((((((((((((((((((((((((

I've got my little scaled K10 with PRC10FR300 and a couple of K3.5 /3FE25 along with my KUBE12 as helper woofer
 

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Here's a rear view of that little 0.62 scale K15. I think when making XKi with a long vent that Nexo's patent (with K-slot shelf vents) might be tested to see if that helps fill in an area for smoother response.
 

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