Foam Core Board Speaker Enclosures?

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Just ordered a pair of the Vifa TC9FD and I'm planning on making the MLTL from the front page! Been looking to build some full rangers and I think this is probably the cheapest way to get my feet wet!
Does anybody know if there is a subwoofer that pairs especially well with these drivers or this MLTL in particular? Will be in a small bedroom in an apartment so I wont need a whole lot!

Are you looking at the flat wall mount MLTL or the bookshelf one? I would also highly recommend the 0.4x Karlsonator that uses a single Vifa. Look in Nautaloss thread for the sub I built with dual 6.5 in high Qts drivers.
 
The bookshelf one, I believe. The version that someone posted plans for, with a front facing port.
Also, while the Karlsonator seems pretty interesting, it seems a bit more complex than I'm looking to do right now. That might be my next foam core project though!
That Nautaloss subwoofer is crazy! Might just be something I'll have to look into down the line. It seems pretty intimidating right now! :eek:
 
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The mini 0.4x Karlsonator is actually very easy if you do it the single piece method where the entire top back bottom front and divider walls is one long continuous piece with creased bends and two sidewalls. I should post a detailed step by step howto.

Anyhow, the bookshelf one you are looking at is very easy to make. You might want to add a baffle step compensation (BSC) circuit to balance the highs with the bass. You will need a 18 gauge 1 mH inductor and a 10 ohm 10 watt power resistor. Wire those in parallel and put between amp and positive lead of driver.
 
Baco99,
Neat project you have there! Can you give us more details like driver model, dimensions and port size? How did you arrive at the design?
:)


Thanks! It's bee interesting. My first foam core project and my first full range project and my first TL project.

Here's a link to the driver I used.
Dayton Audio RS75-4 3" Reference Full-Range Driver 4 Ohm

Someone at Audiokarma helped with the design. Here's a pic of the box before adding the fill.

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


This is based on a single fold voigt pipe design. Here's the page: Transmission Line Speakers

NOTE: This driver, with such a high Fs, will never get deep bass. The program gives me 95, +/- 3bd from the port.
 
Baco99,
I can't see your photo of the internals. The Dayton RS75-4 is a nice driver - good choice. Can you tell us the width, height, depth, and vent height?
Thanks,
X

Sorry the image keeps dropping off.

Here are the dimensions.

Cut Sheet based on 3/16"x20"x30" foam board from a Dollar Store.

4@ 4 5/8" x 27" Front (Doubled)
4@ 4 5/8" x 28" Back (Doubled)
2@ 4 5/8" x 21" Throat (Middle partition)
4@ 28" x 10" Sides
4@ 5" x 10" Top & Bottom


TQWP.jpg


cutting out the parts. No sawdust!

14394931175_1a0ae6bc18_b.jpg
 
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Amazing Masters of Aerial Foam Core!

I knew you could make RC planes but never realized they looked this good and work this well. I should have realized, similar to speakers, the planes are clean and fast to build from scratch. Of course, hot melt glue is instrumental to this. What is cool is seeing all the different construction techniques to get curves, folds, joints, spars, ribs, bracing, etc. Plans are free...

Spitfire Build:
https://www.youtube.com/watch?v=gutkh30I-eM

Go to 4:15 to see it fly, and 9:50 to see acrobatic manuvers:
https://www.youtube.com/watch?v=5A_HJXmwLQ4

Main channel:
https://www.youtube.com/channel/UC9zTuyWffK9ckEz1216noAw
 
Thanks Baco99 - very nice. How do you like the sound and can you get us a sample sound clip?
X

I wouldn't know the first thing about getting a sound clip. Without the baffle step circuit, the bass falls steeply after about 250 Hz or so. Although the software says 95Hz. The high end seems to drop after 14kHz. So, I wouldn't call it a true "full range." I think the unencumbered midrange is really nice to hear. I noticed some artifacts in mixing that I never noticed before and an octave harmony in one song by Daughter that I had also never heard before. Coupled with a subwoofer and a super tweeter, this could be a very competent driver.

The guy who designed this box for me is also working on one with a dual port.
 
OK I guess I was over thinking it lol I just doubled up the foam core on the inside and used some little screws I had around.
These things sound fantastic! Not a whole lot going on in the lower frequencies, but the mids sound great! I never made a baffle step circuit for it though. What exactly will that do for me? I think I might actually build these into a proper enclosure

Listening to Closing Time by Tom Waits on my freshly restored AR XA via Realistic STA 77. Very glad I decided to try this out!