It sounds great on a desk (mine faces a wall) 2 ft away. Very good clarity and the angle that the driver aims upwards is perfect to hit your ear height. One thing I did not expect was the amount of bass that couples to the table surface and vibrates it. You can feel the bass on the desk surface. Not used to that much bass with my cheap PC speakers. I also tested this with my tiny TPA3110D2 amp from Sure ( at PE for $10 ) it is 8 watts and at 30% volume on my iPhone it is more than loud enough. I would guess it is 2 watts - which makes sense 88 dB at 1 m and this is less than 1 m so it is 89 dB which is about as loud as I listen to for casual music listening. You are in for a real treat. They sound wonderful !
re:BOFU -its quite a bit weaker on top than extended wideband so a helper or lower crossover K-tube tweeter could be of benefit. A one inch diameter K-tube could be made of pvc or even rolled paper. Below shows a clone of a 1960's X15 K-tube on top of a K10 size coupler loaded with BOFU and also in an 18 inch coupler. My rough K5 used a cheap MCM 5" "monitor" speaker.
I want to thank XRK971 for appreciably furthering interest in the Karlson concept. Although the "objectivist" may wince, it can be a great way to get music into a room (or open space)
Pioneer BOFU vs Nirvana stamped frame Super8 - both on-axis and in a Druid size MLTL
BOFU in a K10 size coupler
41.5" tall coupler for 18" and 15"
I want to thank XRK971 for appreciably furthering interest in the Karlson concept. Although the "objectivist" may wince, it can be a great way to get music into a room (or open space)
Pioneer BOFU vs Nirvana stamped frame Super8 - both on-axis and in a Druid size MLTL
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BOFU in a K10 size coupler
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41.5" tall coupler for 18" and 15"
An externally hosted image should be here but it was not working when we last tested it.
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I am glad to further the cause on something that sounds this good - people just have to try and be amazed. The small scale foam core makes it easy and inexpensive to try out. I can only imagine what a full scale box with a nice driver sounds like. Thanks to you Freddi for keeping us aware of the K and its variants all these years.
Two amazing values in the world of DIY for $10 ea
It's interesting how the price of the Vifa driver now matches the price of the Sure-built TPA3110D2 amplifier. This amplifier sounds superb - don't let the low price fool you because it has some of the cleanest highs and a nice bottom end with excellent imaging. Match these together and for $30 and your pick of a cabinet - you now have a sound system that will blow away any expectations of what a budget system hould sound like. Although I say desktop system just because of the credit card size of the amp (it will easily fit inside the 0.4x Karlsonator or any enclosure) - it is still powerful enough to full an average size room with great sound.
The Vifa TC9FD and the TPA3110D2 - a great pair. 🙂
It's interesting how the price of the Vifa driver now matches the price of the Sure-built TPA3110D2 amplifier. This amplifier sounds superb - don't let the low price fool you because it has some of the cleanest highs and a nice bottom end with excellent imaging. Match these together and for $30 and your pick of a cabinet - you now have a sound system that will blow away any expectations of what a budget system hould sound like. Although I say desktop system just because of the credit card size of the amp (it will easily fit inside the 0.4x Karlsonator or any enclosure) - it is still powerful enough to full an average size room with great sound.
The Vifa TC9FD and the TPA3110D2 - a great pair. 🙂
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That's an interesting idea X. Powered 12" high Karlsonators. Sounds like a great protable system ah?
Am I seeing right. It looks like the woofers is totally blocked off from the rear wave by that horizontal brace on the back side of the wings just above the woof.
Would that be needed if I built the cabs out of .5" MDF???
I am thinking about burally maple veneed for mine.
Am I seeing right. It looks like the woofers is totally blocked off from the rear wave by that horizontal brace on the back side of the wings just above the woof.
Would that be needed if I built the cabs out of .5" MDF???
I am thinking about burally maple veneed for mine.
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Djn,
No, you don't need that brace if you are using a sufficiently stiff material like 0.5in mdf. It doesn't block the whole passage as it is about 0.75 in tall and depth of front chamber is about 2in.
No, you don't need that brace if you are using a sufficiently stiff material like 0.5in mdf. It doesn't block the whole passage as it is about 0.75 in tall and depth of front chamber is about 2in.
8 watts to power a 83 - 85dB driver? Sounds like strictly nearfield? Or maybe you mean in mono and one per channel, which would give you around 15 watts.
Still not a lot, but enough for moderate levels.
0.47x scale Karlsonator with Alpair 10.2
I had a request to see how well an Alpair 10.2 would work in a Karlsonator. Based on the size and optimizing for a smooth response, a 7/15x or 0.47x scale works well. Looks like it could be a great sounding speaker - just watch the cone excursion below 60 Hz.
SPL vs Freq, Impedance, Cone Displacement, Impulse response below.
I had a request to see how well an Alpair 10.2 would work in a Karlsonator. Based on the size and optimizing for a smooth response, a 7/15x or 0.47x scale works well. Looks like it could be a great sounding speaker - just watch the cone excursion below 60 Hz.
SPL vs Freq, Impedance, Cone Displacement, Impulse response below.
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On your first graph, what is happening at 300hz? I've seen that same raise/dip on all the graph for the Karlsonator.
does the Karlsonator want high medium low Qts?
does the Karlsonator want high medium low Qts?
I suggest you still use bracing behind the wings, perhaps a 0.5" hardwood dowel, between the vertical division and the seemingly floppiest point of each wing.
All Karlsons are band-pass devices. What we see here is the typical dip at the upper limit of the gain bandwidth. The K-slot allows for output above this, but there is some cancellation going on over a couple of octaves above this gain bandwidth, which can span 2-3 octaves itself.
Regular Karlsons really want low Qts, 0.25-0.35 usually simulates good. The taller versions discussed here with longer folded paths can likely do with 0.35-0.45. The scaled-down versions with small drivers might get away with even higher.
IG
hi X
thanks a lot for the sims. 0.47x is way smaller than the MLTL that i have currently. wonder if its bass response will match with that of MLTL!?
Thanks IG. I like the idea of a dowel. I have a couple feet of .5" walnut on the shelf that will work perfectly. SO? is that cancellation easily decernable? That is about a 15db dip.
It depends on the MLTL design - but my guess is that a MLTL properly designed will let the A10.2 reach a good 45 Hz or so - so it will be deeper. The Karsonator if at full scale of 30 in tall also reaches 40 Hz. When scaled to 0.47x - the path is essentially cut in half - this is needed to match the Qts/Vas of the A10.2. If you ran qnty 2 A10.2's per speaker you could run a full size Karlsonator and get the deep bass. The Karlsonator has other advantages that make it sound, in my opinion, better than a direct radiator MLTL tuned to the same bass extension. This results from the improved dispersion/directivity, and the dynamics (impulse response).
Which MLTL design are you using?
In my opinion, the dip is not an issue in listening to music. It also is not as deep when measured compared to the sims.
Here is a sim of the TC9FD with the mic (your ear) at 24 in away - near field use, and the desk 60 in away from a wall. With room reflection effects turned on, the dip is not as bad - quite narrow so it is not very discernible.
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Thanks X. My desk is right up against the wall so that should help with bass as well. With 4 subs at my disposal, bass really isn't an issue anyway. That dip looks tolerable. This would be a much easier build of xmas wasn't just around the corner. Getting to busy closing out the year.
for a quick build and tryout, i have vifa coaxials with me.
Speaker Stuff
these are 4" mid and 3/4" silk dome coaxials.
however, no specs are available. 🙁
Speaker Stuff
these are 4" mid and 3/4" silk dome coaxials.
however, no specs are available. 🙁
interesting little driver Sound. Mounting might be a pain but doable. Can't wait to hear your impressions.
