Khornukopia

Looks good. Should get better as you add more of your high quality Poly-Cylindrical Diffuser and LF Absorbers.

Most subwoofers are powered with energy efficient Class D amplifiers. I just gave away some normal size subwoofers that I bought over the years and upgraded. Should have just bought huge multi subwoofers in the first place and saved the time and money. Large or small subs use about the same amount of electricity, and the big subwoofers sound better.

Both of your comments got me wondering about these 3-D cellulose wall tiles I planned to attach onto the inside of my garage door. The speakers are in the corners flanking the garage door. Do you think the small concave surfaces on these tiles will have a negative effect on the music in the room, which is currently sounding very fine?

The original subwoofer pair above the Klipschorns were boosted +6db @25hz and hi-passed @20hz according to JBL recommendation, and put out solid bass down to 22hz. Now with the Ultimax 18 drivers in the same 8 cu.ft. ported cabs and an 18hz hi-pass filter, the response is powerful down to 18hz. It is a noticeable improvement. I think it is a good idea to hi-pass all subwoofers, so they are not wasting energy on sub-sonic signals outside of their useful frequency response.

If your Klipschorns have the K-55-M, it might have a similar buzz as the one discussed in this other thread.

Is that a suggested dimension for a certain frequency range? Your radius cuts look perfect, did you CNC those end pieces?

Your well-built diffuser/absorbers look to be about 3 feet tall in your pictures. Will they sit on the floor, or is it recommended to place them at mid-wall height? How far will the mass loaded vinyl back side be spaced away from the wall?

Looking good.

Very interesting project. I have a few questions, but they will probably get answered as you post more pictures and descriptions as your work progresses, so I will be paying attention.

The Mahogany Klipschorns you picked up a short while back are really beautiful and needed to be with someone who appreciates fine speakers.

22 X 10 mid range horns with 1 3/8"-18 TPI from Parts Express. Second and third photos show a K-401 next to it for a side by side comparison.

Yes, your picture does show it better. It looks like we both used the same method for the easy fix.

The high X-max subwoofers probably benefit from a serious break-in session, but I did not want to be in the house during that simulated earthquake. So I turned them up and hopped on my bike for a good long ride around the neighborhood.

That got me interested in the Ultimax 18" subwoofer drivers, so I bought a pair last week. The Ultimax's work really good in my big JBL cabinets.

I simply placed a bead of black silicone sealant along the edge of the black plastic cap. That fixed the buzzing problem and has held up for years.