Here's a new Unity horn project I've been working on. This project is designed to improve on some challenges that I had with my last two projects. (see 1,2)
As I see it, the ideal loudspeaker would play from 20hz to 20khz, from a single point in space, with unlimited SPL.
We want the sound to radiate from a single point in space, because that will yield three improvements:
1) The sound that's reflected from the room will be consistent with the sound that's radiated from the loudspeaker, similar to how instruments behave in the real world.
2) Having the sound radiate from a single point in space improves the intelligibility. For instance, in a conventional loudspeaker, the midrange is radiated from two points in space: the tweeter and the woofer. Because the sound in a conventional speaker radiates from a woofer and a tweeter, this makes it more difficult to understand what people are saying. (intelligibility.) This is one of the reasons that full-range speakers sound so great in the midrange.
3) Having all of the sound radiate from a single point in space, in-phase, improves the imaging.
These three principals are a big part of the "why and how" of my speaker designs, and this project is intended to improve on this foundation.
If you like the sound of full-range speakers, or Unity horns, or the Kef coincident speakers, you might like the sound of Celilo.
Here's some sims of the new waveguide.
There's a few improvements at work here, compared to my last two projects (1,2)
The "Unitized Image Control Waveguide" project was designed to cram a three way Unity horn into a reasonably sized package. In a nutshell, the idea was to create something similar to Danley's Lambda Unity Horn, or Waslo's Cosynes and Small Syns, but in the smallest footprint possible. My reference speakers at this time are Waslo Cosynes.
The UICW worked pretty well but I didn't like how the enclosure looked, and I thought it might be possible to simplify the thing. Basically create something that performed as well, was easier to build and cost less.
That led to the Metlako project, which wound up being something like seven different speakers. The idea with Metlako was a Unity horn with comparable bandwidth to the Lambda Unity Horn or Waslo's Small Syns, but using 3-5 drivers instead of five or six. Basically extending the bandwith of the midranges, so that dedicated midbasses aren't required.
That worked pretty darn well, particularly the later ones.
My big issue with Metlako was trying to figure out the enclosure. In my house, I have the Cosynes all the way into the corners. I wanted to come up with an enclosure for Metlako that would fit snugly into the corners. I had a heck of a time coming up with an enclosure that would work. If you use a rectangular box, it won't fit into the corners well. If you add some angles to the box, it gets difficult to build, particularly if you're terrible at building boxes, like I am.
I tried using a cylinder for an enclosure, but it was difficult to get the waveguide to fit straight.
Due to my challenges making a box that fits in a corner, I took a different approach, which is to make a waveguide that's aimed off-axis. Basically you can put the waveguide in a conventional box, and it will be cross-fired, because the waveguide itself is cross fired.
Here's a cutaway of the new horn. As you can see, it's aimed OFF axis.
The woofers are MCM 55-1870, same as Metlako. I moved the mids to the top and the bottom, because that improves the horizontal polars.
One *significant* improvement, is that Celilo uses a 16mm throat, instead of a 25.4mm throat. The use of a smaller throat improves the high frequency polar response.
In summary:
Celilo is designed to improve on Metlako and UICW. All three speakers are designed to deliver excellent imaging and intelligibility, at an affordable cost.
For some background, the UICW is here, Metlako is here,[/ur] and my 3D printed compression drivers are [url=https://www.diyaudio.com/forums/multi-way/317125-diy-compression-drivers.html]here.
As I see it, the ideal loudspeaker would play from 20hz to 20khz, from a single point in space, with unlimited SPL.
We want the sound to radiate from a single point in space, because that will yield three improvements:
1) The sound that's reflected from the room will be consistent with the sound that's radiated from the loudspeaker, similar to how instruments behave in the real world.
2) Having the sound radiate from a single point in space improves the intelligibility. For instance, in a conventional loudspeaker, the midrange is radiated from two points in space: the tweeter and the woofer. Because the sound in a conventional speaker radiates from a woofer and a tweeter, this makes it more difficult to understand what people are saying. (intelligibility.) This is one of the reasons that full-range speakers sound so great in the midrange.
3) Having all of the sound radiate from a single point in space, in-phase, improves the imaging.
These three principals are a big part of the "why and how" of my speaker designs, and this project is intended to improve on this foundation.
If you like the sound of full-range speakers, or Unity horns, or the Kef coincident speakers, you might like the sound of Celilo.





Here's some sims of the new waveguide.
There's a few improvements at work here, compared to my last two projects (1,2)
The "Unitized Image Control Waveguide" project was designed to cram a three way Unity horn into a reasonably sized package. In a nutshell, the idea was to create something similar to Danley's Lambda Unity Horn, or Waslo's Cosynes and Small Syns, but in the smallest footprint possible. My reference speakers at this time are Waslo Cosynes.
The UICW worked pretty well but I didn't like how the enclosure looked, and I thought it might be possible to simplify the thing. Basically create something that performed as well, was easier to build and cost less.
That led to the Metlako project, which wound up being something like seven different speakers. The idea with Metlako was a Unity horn with comparable bandwidth to the Lambda Unity Horn or Waslo's Small Syns, but using 3-5 drivers instead of five or six. Basically extending the bandwith of the midranges, so that dedicated midbasses aren't required.
That worked pretty darn well, particularly the later ones.

My big issue with Metlako was trying to figure out the enclosure. In my house, I have the Cosynes all the way into the corners. I wanted to come up with an enclosure for Metlako that would fit snugly into the corners. I had a heck of a time coming up with an enclosure that would work. If you use a rectangular box, it won't fit into the corners well. If you add some angles to the box, it gets difficult to build, particularly if you're terrible at building boxes, like I am.
I tried using a cylinder for an enclosure, but it was difficult to get the waveguide to fit straight.
Due to my challenges making a box that fits in a corner, I took a different approach, which is to make a waveguide that's aimed off-axis. Basically you can put the waveguide in a conventional box, and it will be cross-fired, because the waveguide itself is cross fired.



Here's a cutaway of the new horn. As you can see, it's aimed OFF axis.
The woofers are MCM 55-1870, same as Metlako. I moved the mids to the top and the bottom, because that improves the horizontal polars.
One *significant* improvement, is that Celilo uses a 16mm throat, instead of a 25.4mm throat. The use of a smaller throat improves the high frequency polar response.
In summary:
Celilo is designed to improve on Metlako and UICW. All three speakers are designed to deliver excellent imaging and intelligibility, at an affordable cost.
For some background, the UICW is here, Metlako is here,[/ur] and my 3D printed compression drivers are [url=https://www.diyaudio.com/forums/multi-way/317125-diy-compression-drivers.html]here.
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