How HFTs and other miniature tuning devices might work?

After living with some SR HFT room tuning devices for about a month now, I only know one thing for sure. They work. Specifically, they seem to work by improving image specificity, which flows on to other areas such as image size, soundstage dimension and finally subjective tonal balance. 

As I listen, I ponder the question of how and why these devices may be doing what they do. I have come up with an answer but it's only speculation. Could it be that...

The sound waves projected from the back of speakers (in my case ML electrostatics) are normally reflecting off the back wall, and then returning to the listener's ears at the listening position. The highest frequencies are the most directional, and they are the frequencies which the listener uses to focus on, as the source of the sound. Normally these highest frequencies would be reflecting off many "spot sources" on the wall behind the speskers.

If a device were placed on the wall which synthesized even higher frequencies from the highest frequencies, then those ultra-high frequencies would become the most directional ones. The mind's focus would then be on the position of that single device, as the source of the sound. Could it be that high frequencies entering the HFT (or similar device) are divided (or dithered) into ultra-high frequencies (perhaps by a grid or mesh), and then projected out of the device, amplified by its horn-like structure? The effect would be to make one "spot source" (the highest frequency source) the focus of attention, rather than many spot sources. All lower frequencies would subjectively appear to originate from the same point source, based upon the detection of the source of the ultra-directional highest frequencies. In that way, the tiny devices could influence image placement and soundstage dimensions.

Showing 3 responses by whostolethebatmobile

Thanks millercarbon. Yes I have noticed the mesh inside HFTs. I also use ECTs and I have one on top of my Kuzma 4-point 9 arm, where it sits very nicely above the pivot. That seems to be an excellent spot for it. If I remove it or move it, the sound quality decreases immediately, and dramatically. I use 8 of them sitting on top of my Moon phono preamp, and another 8 on the SR PowerCell 12 UEF SE. Also on my Prima Lunas, but fewer and not too close to the tubes. I wouldn’t think of removing any of them as I’m not a masochist!

While the HFTs work on the walls, I don’t like to use too many of them. I only use one dead center, one at the back of the listening position and one one each side wall, behind the speakers. I used a lot more at first, and the effect was so strong that I did not feel at home in the room. It was too alien and detached from visual reality. Using a minimal amount of HFTs is more to my taste, and really helps focus the sound.
Geoff, perhaps the bowls when excited by music also emit extremely high frequency resonance that is able to attract the ear/mind to a point source which helps to enable focused attention. I’m only speculating, but since it appears no-one has provided a definitive explanation, the option to speculate remains open. :-)