Nice! I'm not sure a spherical shaped housing is necessarily producing a spherical shaped wave fornt - so acoustically not the same behaviour as this contraption - if it works (it seems to) - to really verify it, more measurements are needed but at the time, I had to leave the location.
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Measurements in this case will not show anything; the human ear and the microphone are completely different receivers.If you look at the measurements above, can you point to the problem that you are referring to?
Mr. Walker did quite OK with ESL63 - about the same principle. On axis it behaved well - I don't recall if I did any off axis measurements - need to check - but as these are bending wave transducers, directivity is very wide so I don't think it is a problem. Maybe I pick up on this again as snow goes away
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With ESL-63 everything is different than in your design, they have an acoustic lens, but for you it is not clear which part of your vertical structure will emit HF.
If you make a sphere, that is, create a time delay for sound from below and above, it will be worse than doing nothing at all.
No physical lens in ESL63 that I know of but it has a few concentric rings driving the membrane that are progressively delayed from the center and out. This makes that, flat square membrane, behave like a point source measurement wise.
From the Quad homage: "In 1981 QUAD announced the ESL 63; a full-range electrostatic loudspeaker based upon two sets of concentric annular electrodes fed through sequential. delay lines. This patented system produces a sound pressure pattern identical to the theoretical ideal of a point source origin. Once again a QUAD electrostatic loudspeaker became the reference standard around the world."
Wiki: A true point source radiates sound equally in all directions.
So measurements of the speakers directivity will prove if it is a point source or not. Vertically a line source is wide but not horizontally - the delayed transducers in my experiment is intended to take make the line behave wide also vertically - summing to a wide transducers in all directions.
So more measurements for me to prove if I succeed with my intention.
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From the Quad homage: "In 1981 QUAD announced the ESL 63; a full-range electrostatic loudspeaker based upon two sets of concentric annular electrodes fed through sequential. delay lines. This patented system produces a sound pressure pattern identical to the theoretical ideal of a point source origin. Once again a QUAD electrostatic loudspeaker became the reference standard around the world."
Wiki: A true point source radiates sound equally in all directions.
So measurements of the speakers directivity will prove if it is a point source or not. Vertically a line source is wide but not horizontally - the delayed transducers in my experiment is intended to take make the line behave wide also vertically - summing to a wide transducers in all directions.
So more measurements for me to prove if I succeed with my intention.
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No, measurements will show you that you have high frequencies at one or another level in different parts of the frequency response, but they will not show what the quality of these high frequencies is.
Imagine that the HF will arrive from the top and bottom of the speaker with a time delay even without your idea, but you only aggravate this interference by delaying these frequencies even more.
In other words, your high frequencies will be very strongly colored, but the microphone will show that the high frequency level is normal.
Imagine that the HF will arrive from the top and bottom of the speaker with a time delay even without your idea, but you only aggravate this interference by delaying these frequencies even more.
In other words, your high frequencies will be very strongly colored, but the microphone will show that the high frequency level is normal.
I don't think thats a correct understanding. It will and the proof is that measurement gating affects the FR meaning that if you take out later arriving energy you see the FR change. Moving the mic say 5cm also change FR. Superposition work for both human and microphone. If you have a cancellation dip, both will "hear" it. Or a peak.
You of course need to measure at the position that you want to know anything about ;-)
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You of course need to measure at the position that you want to know anything about ;-)
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This is done in an elementary way, place a board 2 meters long vertically, determine a point at the listening position (chair), take a tape measure and measure the distance from the top of the board, its bottom and center to the point of the conventional ear in the chair and everything will become clear and understandable to you. Different distances from sections of the board to the conventional ear (point) in the chair, this will be the “delay time” of the same frequencies, in our case HF.
And this, in turn, means that you will have interference in the HF, that is, a very large color.
And this, in turn, means that you will have interference in the HF, that is, a very large color.
If you intend to say that a speaker measure differently in different positions for the mic this is of course true. Compare these two measurement (not the speaker discussed here! - absolut levels may not be correct) same speaker same room, different mic positions.
You seem to discuss the path length difference between the floor bounce and the direct sound - that typically effect the region around 300 Hz - and not HF really.
I don't understand what this "board" is - sorry.
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You seem to discuss the path length difference between the floor bounce and the direct sound - that typically effect the region around 300 Hz - and not HF really.
I don't understand what this "board" is - sorry.
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Of course, I mean only direct sound.
Of course, here we need to keep in mind many factors, from what distance the measurement takes place, whether there are absorbers in the places of the first reflections, etc., but this is not relevant to the issue under discussion where a vertical emitter reproduces HF from its entire length at different times in relation to the ear sitting at a listening distance.
Of course, here we need to keep in mind many factors, from what distance the measurement takes place, whether there are absorbers in the places of the first reflections, etc., but this is not relevant to the issue under discussion where a vertical emitter reproduces HF from its entire length at different times in relation to the ear sitting at a listening distance.
Thanks!! It was not really an effort to build myself a pair of new speakers - rather investigate something I have been curious about. I might pursue it further - haven't descried of the yearly speaker project yet 
I know briefly about that publication - I think it delves into level shading while the was exploring time shading.
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I know briefly about that publication - I think it delves into level shading while the was exploring time shading. //