Mini Karlsonator (0.53X) with Dual TC9FDs

I just looked at the specs and they are only 83db efficient. That is pretty low for a 5 wpc amp.

With mid/upper bass gain from the Karlson and nearfield listening, 5WPC should be pretty decent IMO. Looking forward to see the build. :)

The only tiny Karlson I've built was the K5, close enough to being dimensionnaly scaled-down from K15, which is probably why it kind of sucked in general. The high-aspect aproach for small drivers make more sense and should yeild better results.

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I just looked at the specs and they are only 83db efficient. That is pretty low for a 5 wpc amp.

TC9FD's are 85 dB efficient. I use them at <5 watts and they are more than loud enough for near field use. Actually you won't need more than 2 to 3 watts for a reasonably loud volume at 1 meter away.

I don't think you will regret these drivers - they are very smooth and have a great flat freq response and reach a true 20kHz.

If you need it louder, run them in parallel at 4 ohms and it will be 91dB at 2.83v. The box will be bigger though - honestly it will be too loud for near field use. If you want to stick with single driver go with the Faital 4FE22 for 91dB.

Good luck with the build - I think you will really like them.
 
I am looking forward to it as well. We should be able to whip these out in a day. In my little home office (12x12) I have 4 subs so I can do the distributed bass thing as well.

If I do need more gain I could use a 12B4 (I think that is the tube) preamp. If the highs are lacking or distorted in any way I could pop my NEO 3 on top too.

Crap, this is becoming complicated!!!

P.S. I could also do the Linkwitz Riely thing in front of the amp to boost the bass as well.
 
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TC9FD's are 85 dB efficient. I use them at <5 watts and they are more than loud enough for near field use. Actually you won't need more than 2 to 3 watts for a reasonably loud volume at 1 meter away.

I don't think you will regret these drivers - they are very smooth and have a great flat freq response and reach a true 20kHz.

If you need it louder, run them in parallel at 4 ohms and it will be 91dB at 2.83v. The box will be bigger though - honestly it will be too loud for near field use. If you want to stick with single driver go with the Faital 4FE22 for 91dB.

Good luck with the build - I think you will really like them.

I'm sure you are right. Thinking back to the last time I had a good system on my desk, I never really CRANKED it up. Right now, funds are tight so I have to go with the $10 specials. I am in the middle of putting an addition on my shop.
 
Djn,
I saw your artwork - great work there. You are pretty handy at making conplex things so I imagine these speakers are child's play. I like your tube amp on stone concept.
Looking forward to seeing how these turn out with your artistic touches applied.
X

Thanks X. If you are talking about the tube amp on light blue marble, that is acturally my Hagarman Octal Cornet. It sounds great.
 
I made that beauty from copper wire and newspaper - re: Klipschorns = hate them in that room - the walls are 3/4" sheetrock over 3/4" plywood on 6" studs with vinyl siding - I can rap my hand on a wall and it will "booommmmmmmmm" for a second or more - the K-horn excites the boom - even on harpsichord - have not listened more than a minute in the last two years. My Heresy Ones with old foil/oil caps are kinder. Karlson sound fab on harpsichord. A couple sheets of plywood to make "false corners" might save the K-horns - but is a mind-F as would also make new K-couplers. I had SpeakerLab K's in the early 70's them birch
K-horns then these lumbercore K-horn bought from a needy friend.
 
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Don't want to hijack the thread - but I built one diy k-horn bottom in the 60s. Just a cheap driver, but when I finished it (~ 10 PM) I put it in the corner and blew my daughters bedroom door wide open. Never did build a second or add a horn, but hope to someday. Probably have to build room with cinder blocks.:D

What's your opinion of the upper registers?
 
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