Mini Karlsonator (0.53X) with Dual TC9FDs

Cut sheet for A1 (can also be used for laser cutting)

Have trawled through the thread and everyone's super useful comments / tips, thanks!!

These are based on BL21DE3 0.4x and build on the one piece internal method from grandcalmar, making the whole wing/case from one piece too

The wing / baffle supports are rotated by 90 deg for materials like cardboard that are strong in only one direction

They're sized for a Visatron FRS8 and P3 material size (slightly smaller than A1) and can be used with Ponoko / Razorlab. If you need the SVG / EPS files PM me.
 

Attachments

  • Karlsonator 0.4x - Internal Wing Top Bottom - P3 v0.11.png
    Karlsonator 0.4x - Internal Wing Top Bottom - P3 v0.11.png
    438.2 KB · Views: 1,526
  • Karlsonator 0.4x - Wing Case - P3 v0.10.png
    Karlsonator 0.4x - Wing Case - P3 v0.10.png
    419.8 KB · Views: 1,491
Founder of XSA-Labs
Joined 2012
Paid Member
Have trawled through the thread and everyone's super useful comments / tips, thanks!!

These are based on BL21DE3 0.4x and build on the one piece internal method from grandcalmar, making the whole wing/case from one piece too

The wing / baffle supports are rotated by 90 deg for materials like cardboard that are strong in only one direction

They're sized for a Visatron FRS8 and P3 material size (slightly smaller than A1) and can be used with Ponoko / Razorlab. If you need the SVG / EPS files PM me.

How cool is that? Thanks!

Perfect demo/project for a class of students to get them an intro into speaker design. Burning Amp etc...

:cool:
 
It's been a really great learning experience so far!

I've submitted the file to razorlab and waiting on them to process and print, will give an update soon

Am hoping the fold and flaps approach will..

  1. replace the need for bracing
  2. result in an airtight enclosure with less effort
  3. compensate for possible tolerance errors in the laser cut

Even with the 0.4x you hit the maximum printing size, but with a slightly bigger material size you'd be able to make the whole case from a single piece

Wow, yeah, supercool. :D

Can't wait to see what this looks like after laser cutting and assembly. The fold method is in some ways more practical than coming up with ponoko file that uses dovetails and tabs.
 
Founder of XSA-Labs
Joined 2012
Paid Member
As I mentioned in another topic, I have a quit lot of loudspeaker units in my basement waiting for a destination. For example four 6.5" units without specifications. Would it be worth a try to put them in a Karlson enclosure or is the risk of a disappointment too high ?

The Karlsonator is much more forgiving than a true Karlson (K15 and variants). You need some idea of whether or not it is a full range or mid bass driver. Whether or not it is high or moderate or low Qts (big or small magnet and is suspension soft or stiff?). Small magnet and soft suspension is probably high Qts, and big magnet and stiff is moderate or lower Qts. You want moderate Qts for Karlaonator. Low Qts for Karlson scaled K15.

6.5in can fit in a 0.53x - a foam core one is easy to try and won't set you back too much other than time (4hrs) if it doesn't work. You can always put a couple of tc9fd's if it doesn't work.

Don't bother making it based in a hunch out of wood though. Not worth it.
 
hi X - did you get around to comparing a K15 bulk Karlsonator to K15 when each use a typical 15" reflex parameter woofer? - my P-Audio 15 coax:

fs = 41.0, Re= 5.3, Le = 0.36mH, Qms = 5.030, Qes = 0.371, Qts = 0.346, Vas = 214.54 liters, BL = 16.4, Mms = 73.3 gm, Sd = 0.0850 m2, Xmax = 3.3mm, eta zero = 3.82%, Hag = 12.0mm, Hvc = 18.5mm
 
Last edited:
Founder of XSA-Labs
Joined 2012
Paid Member
yes - the same external bulk -same 15 (woofer, coax, Nirvana ferrite 15) - it won't look much bigger than a Karlsonator12 in size - assuming same proportions that would be ~1.1 scale


Freddi,
Here are the sims for the P-audio driver with a K15 and 1.10x scale Karlsonator.

K15:

448011d1415681867-mini-karlsonator-0-53x-dual-tc9fds-k15-v3e-p-audio-15cx-freq-1m.png


1.1x Karlsonator:

448012d1415681867-mini-karlsonator-0-53x-dual-tc9fds-ktl7a-p-audio-15cx-freq-1m.png


I think the K15 looks better in terms of bass punch, but the Karlsonator has a smoother roll-off that might sound more hi-fi.
 

Attachments

  • K15-v3E-P-audio-15cx-freq-1m.png
    K15-v3E-P-audio-15cx-freq-1m.png
    31.7 KB · Views: 1,010
  • KTL7A-P-audio-15cx-freq-1m.png
    KTL7A-P-audio-15cx-freq-1m.png
    32 KB · Views: 1,014
hi X - thank you very much for the simulations. I'm somewhat surprised to see the Karlsonator performance fixing its bulk at K15. K15 has a lot of punch, but not seen it solid to 50Hz in half-space. Karlsonator 12 with 10 or 12" is good to 40Hz. I may want a Karlsonator10 for Beta10cx but perhaps that would give up too much low end. (?)

did you keep Z plots for the two simulations? - I assume the 1.1 Karlsonator is tuned around 1/3 octave lower than K15 (?)


mic on ground - cabinet upright
An externally hosted image should be here but it was not working when we last tested it.
 
Founder of XSA-Labs
Joined 2012
Paid Member
Freddi,
The Karlsonator likes a moderate Qts driver for good bass extension. The low Qts has a slow roll off. In a K15 however, low Qts is king. I can get you predicted impedance plots non problem. The P-audio may also like to have more volume - is your 1.1x scale accurate?

Your measurements show a bass roll off starting at 100Hz. Is that comparable to other drivers you have? I seem to recall a K15 having no problem hitting 60Hz.
 
Last edited:
stamped frame Super10 in a 70 liter reflex tuned to 41Hz
a friend's reaction summed up how it sounds in a reflex tuned this low (he gestured to toss it out the window)
it can use BSC and probably tuning like David D. recommends to get a better balance.

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


Karlsonator 6 plan by Greg B. was used for the prototype some years ago http://i.imgur.com/xp0P8go.png

xp0P8go.png


Karlsonator12 fitted with an 8" Visaton BG20 - its ugly with those screws and upper screw spacing but could look decent with a better choice of screws such as chrome washers with black drywall screws or large head furniture assemblyscrews. It sounds really good in my opinion with the original Super10 other than Super10's inherent roughness and that is likely tameable with a bit of felt on the inside of the wings.

An externally hosted image should be here but it was not working when we last tested it.
 
Founder of XSA-Labs
Joined 2012
Paid Member
Ok so I bought some 1/4 inch MDF and have drivers on the way, still looking for the dimensions for the 0.4x version :).

The first post has an index of all the plans. It can be found here:
http://www.diyaudio.com/forums/full-range/239338-mini-karlsonator-0-53x-dual-tc9fds-56.html#post3880182

We have Blaides to thank for the nice drawing. Which drivers did you get, the TC9's or the 3FE25's?

Foam Core is at Dollar Tree, or similar dollar stores, for you guessed it, $1 ea. you can also get thicker more durable (but harder to cut) Elmer's foam core which is really nice and about 3x as heavy as dollar store stuff. That is at Michael's and the like.

Good luck!
 
Founder of XSA-Labs
Joined 2012
Paid Member
stamped frame Super10 in a 70 liter reflex tuned to 41Hz
a friend's reaction summed up how it sounds in a reflex tuned this low (he gestured to toss it out the window)
it can use BSC and probably tuning like David D. recommends to get a better balance.

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


Karlsonator 6 plan by Greg B. was used for the prototype some years ago http://i.imgur.com/xp0P8go.png

xp0P8go.png


Karlsonator12 fitted with an 8" Visaton BG20 - its ugly with those screws and upper screw spacing but could look decent with a better choice of screws such as chrome washers with black drywall screws or large head furniture assemblyscrews. It sounds really good in my opinion with the original Super10 other than Super10's inherent roughness and that is likely tameable with a bit of felt on the inside of the wings.

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

Very nice. The Jessman comes through again. What do these cost to ship from WA to WV? :)
 
The first post has an index of all the plans. It can be found here:
http://www.diyaudio.com/forums/full-range/239338-mini-karlsonator-0-53x-dual-tc9fds-56.html#post3880182

We have Blaides to thank for the nice drawing. Which drivers did you get, the TC9's or the 3FE25's?

Foam Core is at Dollar Tree, or similar dollar stores, for you guessed it, $1 ea. you can also get thicker more durable (but harder to cut) Elmer's foam core which is really nice and about 3x as heavy as dollar store stuff. That is at Michael's and the like.

Good luck!
TC9FD, I had one look at foam core (they didn't have the right size at HD, should have gone to a michael's, next time) and I didn't think it would be sturdy enough to not crumble. After I prototype it I may build future ones out of the foam, to speed the building process if I do it again.

I'm looking forward for parts to come so I can start. Oh and I will hopefully be laser cutting the baffle so we'll see how that goes.