Mini Karlsonator (0.53X) with Dual TC9FDs

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0.53x with Dual 3FE25-16's in Stereo

Assembly of the second channel went much faster as expected since all the thinking was worked out already. I only have one coat of boiled linseed oil (sanded when wet with oil), and it looks beautiful - smooth and satiny and deep natural color of the wood. It's not oily feeling anymore and dry to the touch. I had to try it out upstairs in the kitchen as the basement now lacks carpeting and is very revererant. Here, the speakers are paired with Hugh Dean's (AKSA) 35w Class A Omega amp (way more power than needed of course, but the amp was already here). Using Amazon Dot as source with an M3 preamp for volume control (my other preamps are all in use elsewhere). Sound is very nice - great vocals and the stereo imaging is excellent even though its not far from back wall.
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Close up detail showing rich color of the finish and the nice square drive socket cap screws (I really like these):
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Thanks, Skylar. It sounds very nice here in the kitchen actually, although mounted on proper speaker stands in a acoustically-treated listening room would be ideal. I have never heard dual 3FE25-16's before. These were something that came out of your deliberations based on my initial suggestions on the ACA short list thread. The tonal balance, midrange and detail are great. I feel compared to dual TC9FD's (4 ohms nominal) had probably more bass but top end was not as good as these.

My earlier, back of the envelope, estimates of 97dB at 2.83v sensitivity seems to be off - they sound closer to 91-93dB. However, that is still really sensitive. They are rated 90dB in the specs (the specs are for 1watt not 2.83v) on the PE website and on the spec sheet. A closer look at the published frequency response graph shows superb top end reach beyond 20khz (which is what I am hearing), but the average SPL is more like 87dB at 2.83v. Since these are 16ohm drivers, it would take 4v to to get 1w into them which is where the 90dB rating came from.

https://www.parts-express.com/pedocs/specs/294-1105-faitalpro-3fe25-16-specifications.pdf

When paralleling drivers, you get two benefits: double the drivers for +3dB, and the impedance is cut in half for double the current or another +3dB for +6dB. So with 8 ohm drivers, you get 4ohms nominal and +6dB, and with 16ohm divers, you get 8ohms nominal and +6dB added to 87dB for 93dB. When I was saying they would be 96dB to 97dB before that was based on the quoted spec of 90dB (I assumed it was at 2.83v but it was at 1w).

So I do want to clarify that these are closer to 91-93dB at 2.83v speakers and not 97db as I thought earlier. But they sound great - very nice balance and super top end and lush vocals.
 
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I love those square drive screws, very user friendly, almost slip-proof too :)

The linseed oil finish is a great way to go with decent plywood, they really do look great! Glad to hear you like them. My foamcore 3FE25-16 duallies really do sound good enough to deserve a nice set of wood cabinets, They still get 14-16 hours of daily use at home, and still with the original flea amplifier.
 
if low Z could be tolerated, then a dual FE206 Karlson or Karlsonator (latter not tuned too low) might be punchy. FE206 in a K12 (Karlson"s Twelve inch enclosure) won't go as low as average BLH but will sound better and more "whole" on percussion as I hear the BLH mouth "thud" arrival later than the BLH's direct cone radiation. (subjectively those sound out of time to me but my BLH experience is very limited - am tempted to try a JBL "Harkness" for a reference)

X - are those "Arauco" plywood? - Arauco also looks pretty with sand and seal shellac but that can get runny. I like BB better mainly as
doesn't get banged up as easily in transit.
 
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I love those square drive screws, very user friendly, almost slip-proof too :)

The linseed oil finish is a great way to go with decent plywood, they really do look great! Glad to hear you like them. My foamcore 3FE25-16 duallies really do sound good enough to deserve a nice set of wood cabinets, They still get 14-16 hours of daily use at home, and still with the original flea amplifier.

That's awesome that you use them that much - a sure indicator of a great speaker is how much we use it.

In case anyone wants to know where to get these screws:
CSH Square & Dri-Lube Modified Pan Head Screw
 
Great build - compliments to the cabinet maker! And the boiled linseed oil really brings out the BB wood grain.

they sound great - very nice balance and super top end and lush vocals.
Thank you X - it is very comforting to know now that the mini Karlsonators can sound so great in wood too. I also found the foam version with these drivers very nicely balanced with an amazing top end and great mids. Even surprisingly low bass detail, but the SPL is lacking.

Now, for some help in the bottom end - would something like this work to tie these mini Karlsonators into a FAST/WAW setup?
Crow - Silver Flute W17RC38 Bandpass Subwoofer Tower - AmpsLab
I love the idea of this sub/helper woofer doubling as a speaker stand.
 
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Great build - compliments to the cabinet maker! And the boiled linseed oil really brings out the BB wood grain.


Thank you X - it is very comforting to know now that the mini Karlsonators can sound so great in wood too. I also found the foam version with these drivers very nicely balanced with an amazing top end and great mids. Even surprisingly low bass detail, but the SPL is lacking.

Now, for some help in the bottom end - would something like this work to tie these mini Karlsonators into a FAST/WAW setup?
Crow - Silver Flute W17RC38 Bandpass Subwoofer Tower - AmpsLab
I love the idea of this sub/helper woofer doubling as a speaker stand.

Adding a subwoofer would definitely help and really make it sound very powerful. The Crow you mentioned would probably work wonderfully. Although you have to check the sensitivity - as I doubt it is 93dB. But if it is powered by it’s own amp and active crossover, it doesn’t matter. As the Karlsonator goes to about 60-70Hz, you could easily use a single non directional HT style sub. I used a $100 Polk PSW10 with my 10F/RS225 FAST speakers and it sounded great. That speaker has a built in plate amp and crossover for the tops. I already had separate speaker stands so that was not needed to be a stand. Also, if XO is below 80Hz and non directional, only one sub is needed. The PSW10 has enough power to shake the house - I never turned it past half max on the volume. It also has a bypass button so you can go to just the tops when you don’t want to wake people up at night with casual listening.
 
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These are the stands I use for my 10F/RS225 FAST speakers - a bit taller than 770mm but very sturdy and well made. They have a channel that can be filled with sand or lead shot of you want more mass. They are aluminum extrusions and cast aluminum base and tops. Good stands transforms a good speaker to a great speaker.

Ultimate Support MS-90 - 36" Tall, Black Finish | Sweetwater
 
If you mean stands for the 0.53X Karls, these Crow - Silver Flutes are not tall enough at 21.75" (552mm). I need around 770mm high stands to bring the Karlsonator drivers up to ear level.

Because the ports are at the top, you just need to give the Crows some 300mm feet. :D

These are the stands I use for my 10F/RS225 FAST speakers - a bit taller than 770mm but very sturdy and well made. They have a channel that can be filled with sand or lead shot of you want more mass. They are aluminum extrusions and cast aluminum base and tops. Good stands transforms a good speaker to a great speaker.

These stands are great - but they don't have built-in helper woofers.
 


Shipping to SA can practically only be by courier. The local PO is useless and IF stuff arrives here, it takes forever.

I think it's safe to say that I will never pay that much for speaker stands. I'd rather make it myself. I'd rather spend $250 on nice speaker drivers! :D