Just finished these speakers last night. Very happy. Some advice for beginners: Draw out X's design to scale on a piece of paper first and measure all the pieces from there to make sure it fits. Helps shake out implicit assumptions 
I'm in Aus, so they were crazy expensive. $11.40 per small sheet of foam core from Officeworks. Took 5 sheets for 2 speakers. The foam core is good quality and it's matte black though so there's that, looks kinda nice. Essential Audio | Australia | Guitar Speakers | Bass Speakers | PA Speakers | Hi Fi SPeakers | Home Theatre | Cabinet Hardware can get the vifa's in and sell them for $25 each, not that cheap but the service was awesome, 2 days shipping.
If I had the space and was doing them again I'd just do them in ply. But I don't have the space, and so am very appreciative of X's design
Next step, find a microphone for tuning them with.
I'm in Aus, so they were crazy expensive. $11.40 per small sheet of foam core from Officeworks. Took 5 sheets for 2 speakers. The foam core is good quality and it's matte black though so there's that, looks kinda nice. Essential Audio | Australia | Guitar Speakers | Bass Speakers | PA Speakers | Hi Fi SPeakers | Home Theatre | Cabinet Hardware can get the vifa's in and sell them for $25 each, not that cheap but the service was awesome, 2 days shipping.
If I had the space and was doing them again I'd just do them in ply. But I don't have the space, and so am very appreciative of X's design
Next step, find a microphone for tuning them with.
GC - So that is how it's done. : )
I understand. Mine is a bit on the tall side.
Then I determinded with X's help not use foam
but board for the bass/mid.
Yeah, I went with 2 driver as that is what I had
bass/mid then tweeter. Boards are drying now.
Put some quick and dirty oil finish on them.
Hopefully in the next week I can finish.
I was forced to relinquish the dinner table
as I've no where else to lay out and work,
and my significant other was well you know.
AND
my assistant was finding little things to eat
and a table top of things she shouldn't touch...
like exactos, etc.
Thoughts at this juncture...
Buy a full range driver (I'd be finished already).
Thinking I'd rather it be in wood. Yet, I feel the
foam is a great rapid prototype method and it preps
you for wood later down the road.
I'm 3/4 there, with the foam.
Francisco,
Any updates in your completed speakers with front aperture securely fastened on? Hope it worked out well for you. If you ever need more power check out the TPA3116D2 amp. You can get really loud with that amp and it would be a simple board swap.
X
Bfabry,
Congratulations! Glad you like them - another happy builder. That is too bad FC is so expensive in Australia. We are really lucky here in the States with dollar store FC and $10 Vifa's. Photos please.
Photos:
I've built a new stereo comprising a pair of foam board Karlsonators with TB W3-881SJF drivers and a TDA7297 amp and 12AU7 Valve Cmoy Headphone for preamp from Fed's Amps.
It is really quite remarkable how remarkable this little little set-up sounds. Thanks again master X for all you guidance.
It was great fun to build- hope you enjoy it
cheers
It is really quite remarkable how remarkable this little little set-up sounds. Thanks again master X for all you guidance.
It was great fun to build- hope you enjoy it
cheers
Attachments
Hi!
prezden and bfabry they look really nice!! Synctronx, with such a good assistant it will surely turn out great!
I've been quite busy these days but I just finished lacquering them!! I'm a horrible woodworker, and spent a lot of time sanding and puttying the cabinets to get everything smooth and professional-looking but I'm really happy with how they turned out. Can't wait to put it all together tomorrow and hear how they sound eventually!! I'll take some pictures and post them here!!!
As per my previous tests, they are way louder than I expected beforehand but anyway I definitely have to try some of these tpa3116d2 amps!!!
Cheers,
Fran
prezden and bfabry they look really nice!! Synctronx, with such a good assistant it will surely turn out great!
I've been quite busy these days but I just finished lacquering them!! I'm a horrible woodworker, and spent a lot of time sanding and puttying the cabinets to get everything smooth and professional-looking but I'm really happy with how they turned out. Can't wait to put it all together tomorrow and hear how they sound eventually!! I'll take some pictures and post them here!!!
As per my previous tests, they are way louder than I expected beforehand but anyway I definitely have to try some of these tpa3116d2 amps!!!
Cheers,
Fran
Prezden,
Those look really cool with the custom hand made paper covers over the Karlson apertures. Also like how your tube preamp in a wooden box looks. How do you like the sound of the tube preamp with tda7297? Surprised you are not going with the 3110? I think you got a 3116 - are you still working on getting that set up?
Fran,
You are in a for a real surprise when you hook up the 3116 amp to your mini Karlsonators. If you think they are loud with the 3110, be prepared to be amazed. Watch out for overdriving them though as those amps can actually put out 75watts/ch into a 4 ohm load with the right power supply. Have fun. Looking forward to seeing the finished product.
Those look really cool with the custom hand made paper covers over the Karlson apertures. Also like how your tube preamp in a wooden box looks. How do you like the sound of the tube preamp with tda7297? Surprised you are not going with the 3110? I think you got a 3116 - are you still working on getting that set up?
Fran,
You are in a for a real surprise when you hook up the 3116 amp to your mini Karlsonators. If you think they are loud with the 3110, be prepared to be amazed. Watch out for overdriving them though as those amps can actually put out 75watts/ch into a 4 ohm load with the right power supply. Have fun. Looking forward to seeing the finished product.
those mini's are really cool! -- hey X - how would GB's Karlsonator 12 do with my heavy duty TSG 12cx? - its not as sensitive as my 1114 Martin 12cx (fave 12cx) but has more xmax - I'm trying to figure out the best match for the Karlsonator 12 - - for some reason Beta 10cx looks great in your sims
TSG 12-1844 COAX 12” inch with 4 Inch Voice Coil
And 1 3/8” Screw on Compression Driver mounting.
EM specs:
Re = 5.52 ohms
Le = 1.68 mH
Qms = 9.95
Qes = .27
Qts = .27
Xmax = 4.8 mm
BL = 17.96 T*M
VC Diameter = 4 inches
Gap Height = 9.52 mm, .375"
No (Efficiency) = 2.75 97 db
Fs = 44.41 Hz
Zmax = 206.1 ohms
Mms = 57.4 g
Mmd = 50.4 g
Cms = .2239 MM/n
Rms = 1.6088 N*sec/M
Sd = 532.36 Cm2
Vd = 253.54 cc
EBP = 162.2
Magnet Weight = 109 oz.
Winding Length = 19.0 mm, .75 inches
Calculated Sensitivity = 97 db
TSG 12-1844 COAX 12” inch with 4 Inch Voice Coil
And 1 3/8” Screw on Compression Driver mounting.
EM specs:
Re = 5.52 ohms
Le = 1.68 mH
Qms = 9.95
Qes = .27
Qts = .27
Xmax = 4.8 mm
BL = 17.96 T*M
VC Diameter = 4 inches
Gap Height = 9.52 mm, .375"
No (Efficiency) = 2.75 97 db
Fs = 44.41 Hz
Zmax = 206.1 ohms
Mms = 57.4 g
Mmd = 50.4 g
Cms = .2239 MM/n
Rms = 1.6088 N*sec/M
Sd = 532.36 Cm2
Vd = 253.54 cc
EBP = 162.2
Magnet Weight = 109 oz.
Winding Length = 19.0 mm, .75 inches
Calculated Sensitivity = 97 db
Last edited:
Freddi,
I will run the sim as soon as I get to my computer. The Qts looks pretty low though not sure how that will work, I seem to recall a Qts closer to 0.4 being more ideal. More importantly, who will build it for you? I recall a DIY forum member offering to CNC for you but you have to cover shipping. Maybe you can take up foam core construction as it is lighter than wielding power tools on heavy plywood.
One thing is for sure: the scaled down mini Karlsonators have been a great success with unanimous happy builders who report that they love the sound.
I will run the sim as soon as I get to my computer. The Qts looks pretty low though not sure how that will work, I seem to recall a Qts closer to 0.4 being more ideal. More importantly, who will build it for you? I recall a DIY forum member offering to CNC for you but you have to cover shipping. Maybe you can take up foam core construction as it is lighter than wielding power tools on heavy plywood.
One thing is for sure: the scaled down mini Karlsonators have been a great success with unanimous happy builders who report that they love the sound.
Last edited:
if that's the case - then perhaps they will get my medium Qts (less sensitive) cast frame ~Delta 12cx custom made for a former Gauss president (or 12LTA or Beyma 12cx with Qt ~0.5). My potential cutter is the guy who made Karlsonator 8s (~2300 miles away so shipping adds up)
(I lost track of the gentleman who offered to CNC)
my favorite EM 12cx - Martinsound's defunct 1114 coax with 80oz magnet and reasonably low mms.
my 54oz magnet Eminence 12cx made like Beta12cx - it has a custom cone and really made for a sealed box.
the little Beyma 12cx's woofer goes higher than the Eminence stuff - the compression driver is something
like an APT50
(I lost track of the gentleman who offered to CNC)
my favorite EM 12cx - Martinsound's defunct 1114 coax with 80oz magnet and reasonably low mms.
An externally hosted image should be here but it was not working when we last tested it.
my 54oz magnet Eminence 12cx made like Beta12cx - it has a custom cone and really made for a sealed box.
An externally hosted image should be here but it was not working when we last tested it.
the little Beyma 12cx's woofer goes higher than the Eminence stuff - the compression driver is something
like an APT50
An externally hosted image should be here but it was not working when we last tested it.
Last edited:
TSG 12-1844 in 12/15 scale Karlsonator
Freddi,
This driver may actually work out alright if you EQ the mids and highs down a bit to flatten the response. Here are the sims for a 12/15x scale and 15/15x scale Karlsonator with the TSG 12-1844 driver. The fullsize gets you solid 90 dB at 45 Hz at 2.83v.
X
12/15x scale:
Fullsize (15/15x scale):
Freddi,
This driver may actually work out alright if you EQ the mids and highs down a bit to flatten the response. Here are the sims for a 12/15x scale and 15/15x scale Karlsonator with the TSG 12-1844 driver. The fullsize gets you solid 90 dB at 45 Hz at 2.83v.
X
12/15x scale:
Fullsize (15/15x scale):
Attachments
22 nano -
I am blessed to have such and assistant, and she takes up
so much time too.
Of course then comes some other projects for the wife, for the house, for the baby, lastly for me.
Had a simple mic amp project talk a bad turn.
Taking a plungefor a different set of karlsonators.
I scored a nice piece of Houndoran Red. 4 x 8 with some with some treatment, they willl look very very nice.
XXXX do I build them with my old pease or do I
I am blessed to have such and assistant, and she takes up
so much time too.
Of course then comes some other projects for the wife, for the house, for the baby, lastly for me.
Had a simple mic amp project talk a bad turn.
Taking a plungefor a different set of karlsonators.
I scored a nice piece of Houndoran Red. 4 x 8 with some with some treatment, they willl look very very nice.
XXXX do I build them with my old pease or do I
Hi!
prezden and bfabry they look really nice!! Synctronx, with such a good assistant it will surely turn out great!
I've been quite busy these days but I just finished lacquering them!! I'm a horrible woodworker, and spent a lot of time sanding and puttying the cabinets to get everything smooth and professional-looking but I'm really happy with how they turned out. Can't wait to put it all together tomorrow and hear how they sound eventually!! I'll take some pictures and post them here!!!
As per my previous tests, they are way louder than I expected beforehand but anyway I definitely have to try some of these tpa3116d2 amps!!!
Cheers,
Fran
Yes, anytime you can get 90+dB efficiency from 1 watt down to 50 Hz that is pretty good in my mind.
Good luck on getting it built! I am sure it will sound fantastic.