Active Horns Acoustical Treatment & DSP

[Bjorn]

It looks to me like it has significant vertical pattern control down to 300Hz based on the measurements posted here: https://data-bass.ipbhost.com/topic/1381-measurements-from-big-cds-and-horns/ I would expect it to because it's huge!View attachment 399352

Quite the contrary. That graph is confirming what I'm saying.
And here's Klipsch own measurement:

The horn isn't big vertically in reagards to the 60° directivity. Horizontally it's much bigger and combined with a wider 90° it's able to remain a constant directivity down to 250-300 Hz area

Below is measurement of a horn that is contant vertically much lower and that's a clear audible improvement as well.

 

[Tim Link]

Quite the contrary. That graph is confirming what I'm saying.
And here's Klipsch own measurement:
View attachment 399449
The horn isn't big vertically in reagards to the 60° directivity. Horizontally it's much bigger and combined with a wider 90° it's able to remain a constant directivity down to 250-300 Hz area
View attachment 399450
Below is measurement of a horn that is contant vertically much lower and that's a clear audible improvement as well.
View attachment 399452

View attachment 399453

I stand corrected! Obviously I'm not good at interpreting charts. The thing I look out for on a plot like that is a non-smooth off axis, or the point where the off axis is as loud as the on-axis. That's a clear sign that there is poor, or no pattern control. On the post I was linking there was still some kind of directivity all the way down to 200 Hz, smoothly transitioning to complete loss of control. Only a big horn could do was well as the K402 vertically, or perhaps a line array of some kind, or planar. It has to be big vertically. It looks to me like the huge horn in the picture has been turned sideways. Is that how it's vertical dispersion was measured? If so, it won't do so good horizontally. The horn is going to have to be as huge in both directions to make them equal. Or is that a square horn just viewed from an angle to make it look taller than it is wide?

 

[Bjorn]

I stand corrected! Obviously I'm not good at interpreting charts. The thing I look out for on a plot like that is a non-smooth off axis, or the point where the off axis is as loud as the on-axis. That's a clear sign that there is poor, or no pattern control. On the post I was linking there was still some kind of directivity all the way down to 200 Hz, smoothly transitioning to complete loss of control. Only a big horn could do was well as the K402 vertically, or perhaps a line array of some kind, or planar. It has to be big vertically. It looks to me like the huge horn in the picture has been turned sideways. Is that how it's vertical dispersion was measured? If so, it won't do so good horizontally. The horn is going to have to be as huge in both directions to make them equal. Or is that a square horn just viewed from an angle to make it look taller than it is wide?

Yes, the horn in the picture was turned side ways to measure it vertically.
Here's it measured horizontally.

This is only the top horn. Together with a midbass horn, it offers a constant directivity both vertically and horizontally quite low in frequency.

Frequency response over a reflective floor changes very little at different heights.

A traditional line array doesn't measure well vertically. The drivers don't sum well at distanced indoor. But a CBT speaker offers a uniform dispersion vertically.

https://www.keele-omholt-technologies.com/

 

[Tim Link]

Yes, the horn in the picture was turned side ways to measure it vertically.
Here's it measured horizontally.
View attachment 399568

This is only the top horn. Together with a midbass horn, it offers a constant directivity both vertically and horizontally quite low in frequency.

View attachment 399569

Frequency response over a reflective floor changes very little at different heights.
View attachment 399570

A traditional line array doesn't measure well vertically. The drivers don't sum well at distanced indoor. But a CBT speaker offers a uniform dispersion vertically.

Wow, very nice! It looks great too. That's the kind of thing I'd be building if I could start over again. Is the flare on that lower horn flat with the floor? That would make sense to me, how I've always visualized doing it.

Keele's method looks intriguing. Makes me wonder if it could be combined into a horn to get control horizontally. That would be a seriously big horn, sort of a giant bi-radial thing. Might call it a giant's butt-cheeks.

 

[Tim Link]

I need an explanation of this graph. Is the red on axis? What are all the other plots. I was assuming they were off axis at various degrees. If so, this would suggest and extremely wide dispersion with low directivity. Is that correct?

 

[Bjorn]

I need an explanation of this graph. Is the red on axis? What are all the other plots. I was assuming they were off axis at various degrees. If so, this would suggest and extremely wide dispersion with low directivity. Is that correct?

Black is on-axis. It's a vertical measurement at different heights above a reflective floor in a living room. More information here: https://www.audiosciencereview.com/...audio-midrange-horn-polar-measurements.42732/

 

[Bjorn]

Keele's method looks intriguing. Makes me wonder if it could be combined into a horn to get control horizontally. That would be a seriously big horn, sort of a giant bi-radial thing. Might call it a giant's butt-cheeks.

The CBT has controlled horizontal direcitivity, but the traditional CBT is wide. Controlled isn't the same as narrow, but means it's constant or uniform. So it can be both wide and narrow. Making it narrow can be done in several ways.