2-way Karlson type

[freddi]

I like slotted tube inside or on top of k-coupler - who else is into building
this Karlson stuff? - that's an 18" lower mass Eminence with 0.25 Qts in the coupler

[PeteMcK]

Hi Freddy, Trad Karlsons are too big for my place - I think the most valuable part of their design - the BR/K slot pipe is a good design for the low end of a hi-eff 3-way system. The K slot itself I think would be valuable in TL terminations....

[MechanicalAnimal]

Oooeewwhhhhh......Karlsons

This is my build of a couple of Karlsons!

It all started with a friend of mine who had 4 of this big mighty speakers in his room in our studentdorm

When he moved i borrowed one pair and then decided i wanted i wanted to build them myself
Each cabinet is equipedd with a 12inch Celestion driver and a cheap-*** piezo-no-name-crappy-tweeter. XO was build by the supplier of the used drivers and i am sorry that i cannot tell you on what freqs the units are crossed or what components are used. Trust me...it's lowbudget.

Most pics are scanned, pre-digicam-era.

SneakPreview


Celestion 12 inch Q12-1735-T4911


Cabinet next to the soon replaced Philips FBserie (good speakers though)


8 billion screws, every 2 inch or so


In hindsight i should have used bracing


Test-setup.........OMG.....what a volume


"Curtains" placed and ready to rock


Finishing was a zero-priority job, so i've had them like this a long time.

2 b continued

[MechanicalAnimal]

Here goes: My Karlson's The Sequel

The original i borrowed were bright yellow, though i choose a bit more practical colourscheme. Black and purple.





Precoat



Predrilling



B/W!



B/P!

Offcourse i wanted that flighcase-look! But...like always....the project disappeard in the deepfreeeeeeeeeeze

[MechanicalAnimal]

Years later......i ordered some aluminium corners and a real digicam!
Side


"Under Construction"


12inch, very nice indeed


Almost there.......


Almost almost there.....


FINISHED....and rocking away with these babies!!!

Things still to do :lol: : Alu on the front and cornerpieces.

[MechanicalAnimal]

soooo.....this is the job i have to still do


Current state


and some random pictures:

inspirator and friend Yør.


In the background his Karlsons, fitted with FANE drivers.
One pair with longthrow and the other with a shorter throw drivers

We were just building my highsleeper-bed and it always DIY better with some music.

His Karlons have since been upgraded...not only a nice oxbloodred finish but the Foster piezo tweeter has been replaced with a hifi-sounding round softdome tweeter in stead of the PA-like-screecher.
With the new XO fitted this sounds much better in comparison with mine.

Some detailed pictures











Hope you enjoyed this

[freddi]

Highly enjoyable ! lively color schemes too ! nice to see tweeters on wings -

Karlson couplers are the wonder of the world (and apparently not popular in US) - you might flatten the piezo with a resistor & small inductor - maybe 0.2mH across it, then a series capacitor.

I'd like some new couplers and not heard that model. I do have a 1955 and ~1958 Karlson 12. Couplers are tough to beat for punch - a slotted Karlson pipe can be used for tweeter.

does the cone motion stay pretty low on your and your friend's couplers?

an internet friend built this little (20"x15"x28") coupler for 15" driver a few years
ago and seemed to be pleased

[MechanicalAnimal]

Originally Posted by freddi

Highly enjoyable ! lively color schemes too ! nice to see tweeters on wings -

Karlson couplers are the wonder of the world (and apparently not popular in US) - you might flatten the piezo with a resistor & small inductor - maybe 0.2mH across it, then a series capacitor.

I'd like some new couplers and not heard that model. I do have a 1955 and ~1958 Karlson 12. Couplers are tough to beat for punch - a slotted Karlson pipe can be used for tweeter.

does the cone motion stay pretty low on your and your friend's couplers?

an internet friend built this little (20"x15"x28") coupler for 15" driver a few years ago and seemed to be pleased

Thanks

i'll think i'll keep them the way they are 'cause i'm planning to build a pair of Avalon Isis-clones

with cone-motion you mean the excursion of the driver?:

Celestion Q 12-1735 T 4911 Thiele/Small
Xmax..............................2.25 mm
Magnet weight................1.035 kg (35 oz)
Thermal Power...................100 Watt
Freq. respons..................65-4k Hz
Total Dyn. mass...................37 gram
Total Q, Qts....................0.504
Mechanical Q, Qms.............6.57
Electrical Q, Qes...............0.545
Sensitivity (dB 1W@1m).........97 dB
Resonance, fs......................62 Hz
Resistance, R........................8 Ohm
Equivalent Vol. Vas............70,7 liter
BL product.......................12.8
Compliance Cms................0.18 mm/N
Mechanical resistance..........2.2 kg/S

as you can see....Xmax is 2.25 mm, so that makes an maximum total of 4.5 mm movement, so cone-movement is somewhat minimal to say the least.

Those 15"cabinets are HUGE!!!

[freddi]

I wondered how much your woofer was moving when playing loud.

Those 15" enclosures are about 1 cubic foot more in bulk than a 12" Karlson.

Here's a !0" size Karlson with 8" coaxial next to a factory 12" Karlson
- do you see any little couplers built?

[w_oswald]

3-way design actually; K-15 cabinet (modified), with EV Wolverine LS-15, EV T-25A on 8HD horn, a pair of Cerwin-Vega horn tweeters, and a somewhat involved crossover.
It was my first (and only - so far!) attempt at a Karlson-based design, and I did some obviously unconventional things with it, as compared to the original design. It allowed me to try out some ideas, and turned out sounding acceptable, considering the "junk-bin" parts I used for it, and looks nice too (at least in my biased opinion).

Wilf