Fast, fun, Inexpensive OB project

Hi all,
I have been following this thread since the beginning. I finally have a location in my basement for a stereo listening area and was going to go with the Ultra's. However, on:
2020-04-16 11:57 pm post #2,169, John wrote about a high performance design - Baffle dimensions are around 19" wide, 12" deep and 40" high. About 45 pounds net. Two way using an 18" and 4.5" (world class Neo).

Any update on this? The baffle being narrower than the Ultra's with larger drivers intrigues me. I think I want to hold out for this design and read a few initial listening impressions compared to the Ultra's.

Thank you
 
Hello DKAudio.. i have designed several upgraded replacements for both the Altra and originanal Manzanita. However, every time I get ready to post a new solution, one or several of the major components are discontinued or rises to an unacceptible price! So, I would stick with the original design as long as it remains a fiscally reasonable option and upgrade as financial abiltity still make sence!
 
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Makes sense, John, except for my already buying the 18inchers.....

(My 123s have a happy home, so they can stay there.)

So, use your basic idea for the baffle, start with the standard lowpass(adjusted where needed for proper behavior), and if I use a pair or quad of TC9s, adjust for impedance and reduce padding. How's that sound? (for a start)
 
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Seemed like it to me.
Anyway, when folks started guessing, in post 2215 you said it was the 06-08 and the 123-08.
I thought the 06-08 made sense, big enough that a lower Q would not be too much trouble, and I had
listened to my 123s alone before using them, so I thought they could be tamed at least into the teens.

If a three-way, I've got lots of potential mids that could keep up with the 18s, and various tweeters with some kind of
horn-loading or waveguide.
 
I for one, am extremely interested in a Super design. I too thought the driver selection was going to be the FSL-1830R06-08 and NE123W-08. I saw a few update posts over the past year and a half stating progress was still being made. By John's reply (#2807) to my post, has this been abandoned? Bummed if so...
 
Folks I have come across a strange situation, I have found that the mids/high was a bit piercing for me when played at soft volume, but when played at high volume sounds great. So what I did I added some resistors, it sounds pretty good for me now at low volumes... However I have added a total of 30 ohms to the vifa tc9... Im wondering now if there is something wrong with my speakers...

Additional info: I have followed the recommended crossover with one exception, instead of the 4.7uF I have used 2.7uF instead.
 
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OK, that makes more sense. That inductor and resistor are used to shape the rising response of the Vifa and make it flatter. The resistor basically controls how much effect the inductor has, whereas the value of the inductor sets the frequency range of the correction. By using a smaller inductor you have moved up the frequency of correction. Using a higher value resistor makes the correction stronger.
 
OK, that makes more sense. That inductor and resistor are used to shape the rising response of the Vifa and make it flatter. The resistor basically controls how much effect the inductor has, whereas the value of the inductor sets the frequency range of the correction. By using a smaller inductor you have moved up the frequency of correction. Using a higher value resistor makes the correction stronger.
I have not changed the 15ohm and the 8ohm resistors, that remains the same, after the 2.7mhinductor which is parallel with the 15ohm resistor, I have added 30 ohms.
15-inch-crossover.png