But you're not listening on axis, more to the power so to speak. Not to mention the HF driver acting as a diffuser.
I don't think that would matter, it happens even on a flat baffle. On the other hand Linkwitz does like to blend a certain amount of room and direct...
so if most of say a french horn comes from the woofer and most of a flute comes through the mid-tweeter this is like pointing the mouth of the horn pointing up vertically while playing the flute right about the mouth of the horn
as opposed to a typical set up where the drivers are on the same plane except for down firing subs
in an orchestra the instruments are of course not set up that way
as opposed to a typical set up where the drivers are on the same plane except for down firing subs
in an orchestra the instruments are of course not set up that way
So how does this weirdly configured speaker compare with say a more conventional tower with a single full range mounted higher and crossed pretty low with a larger woofer at the bottom of the tower that could also be down firing ?
I can only guess that Linkwitz has chosen to put more energy into the room for a given on axis level. I might assume he has done a fair job of balancing that too, despite the looks. Regardless of whether an instrument is played more by the lower driver or the upper, I like to ensure the crossover blends.
if the box was as small as with pluto (for the fullranger) then not much, except you cant do that or the woofer would be quite far away if it was downfiring. If there is big box for the woofer and the fullranger is on side of that then the response of the fullrange driver is narrowed some on shorter than baffle size wavelengths and it would have edge diffraction ubless roundover edges. Quite different polar response.
To me the Pluto is just minimal diffraction construction, and omni to quite a high frequency, no diffraction until very high frequency. If you had the drivers on a flat baffle the response would narrow lower in frequency and then diffract all the way up to where the fullranger beams.
Minimal, Pluto has lot less diffraction than a shoe box simply because it has less length of baffle edge.
The woofer is probably crossed over to the "tweeter" before the tweeter structure in front of it is acoustically big so not much diffraction happens on the woofer.
About only diffraction that happens is with the "tweeter" and this is at very high frequency because the tweeter baffle is small, practically non existent, and only main diffraction hump is there but not much else from "baffle". There would be some from the woofer structure as it is nearby and the tweeter is pretty much omni directional up to high frequency but I'm not sure how much this would be, I'd suspect not too much.
The woofer is probably crossed over to the "tweeter" before the tweeter structure in front of it is acoustically big so not much diffraction happens on the woofer.
About only diffraction that happens is with the "tweeter" and this is at very high frequency because the tweeter baffle is small, practically non existent, and only main diffraction hump is there but not much else from "baffle". There would be some from the woofer structure as it is nearby and the tweeter is pretty much omni directional up to high frequency but I'm not sure how much this would be, I'd suspect not too much.
I would disagree that this is how it works, and in any case it isn't that simple.
If you take a transducer and put it to various sized baffles you will notice this is precisely how it works, no matter how you define diffraction being more or less, its relative and inspecting it from a frequency response is quite easy. Its easy to see when there is more or less ripple on the response. The bigger the baffle in comparison to the transducer the more ripple. More flat area, longer edge, which ever feels handy.
We are mostly interested what happens in the listening window but the similar thing happens to any angle you inspect at, sound propagates to all directions, you could inspect frequency response to back, or to side, or a polar map, what ever you'll see less ripple, which means less interference which means secondary soundsource(s) have less effect, narrower bandwidth and/or amplitude.
Frequency response shows response over time, this means that if you have two ideal flat amplitude response sources playing at the same time but delayed slightly this will show a combfilter. Exact same thing happens with diffraction except the second sound source is more compex as you say. Still on a frequency response just a ripple due to delayed sound, the whole edge becomes a secondary sound source. When the edge is about the same size as the transducer itself there is no difference, except the diffraction making opposite polarity source, the diffraction is minimized. Only way to get even less is to put the transducer on a sphere, or approximation of one.
If you play with this in a simulator its very easy to come up with these simple observations and draw conclusions. I cannot imagine exactly what the output response would look like but its not too hard to imagine when there would be more or less diffraction.
We are mostly interested what happens in the listening window but the similar thing happens to any angle you inspect at, sound propagates to all directions, you could inspect frequency response to back, or to side, or a polar map, what ever you'll see less ripple, which means less interference which means secondary soundsource(s) have less effect, narrower bandwidth and/or amplitude.
Frequency response shows response over time, this means that if you have two ideal flat amplitude response sources playing at the same time but delayed slightly this will show a combfilter. Exact same thing happens with diffraction except the second sound source is more compex as you say. Still on a frequency response just a ripple due to delayed sound, the whole edge becomes a secondary sound source. When the edge is about the same size as the transducer itself there is no difference, except the diffraction making opposite polarity source, the diffraction is minimized. Only way to get even less is to put the transducer on a sphere, or approximation of one.
If you play with this in a simulator its very easy to come up with these simple observations and draw conclusions. I cannot imagine exactly what the output response would look like but its not too hard to imagine when there would be more or less diffraction.
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You can't judge diffraction by response. Your simulator does not show diffraction, it shows response.
For sure can estimate when there is more or less. Axial response shows the most effect and polar data shows more complete picture. It is enough to know when there is more or less, to minimize the ill effects of it. In addition to looking at the response one needs to consider it in the whole speaker concept as there are crossovers that can split the band to another transducer to reduce problems.
What I cannot tell from these is how audible the stuff is but here again its relative, if there is ripple in response its more likely be audible than when there is not.More over the diffraction effects appear in the response right where one needs crossover and judge how to make the filters, the response is very much affecting the outcome of any given system.
What I cannot tell from these is how audible the stuff is but here again its relative, if there is ripple in response its more likely be audible than when there is not.More over the diffraction effects appear in the response right where one needs crossover and judge how to make the filters, the response is very much affecting the outcome of any given system.
I need to add that if you are thinking and looking at real driver measurements and especially only single axis frequency response, it might be hard to differentiate between effects of diffraction and other issues like cone breakup. However if you inspect this stuff with ideal driver effects of diffraction are plain visible and easy to judge.
Frequency response of idela transducer would be flat (sans beaming) if it was only direct sound from the transducer. Any deviation from this is due to at least one another delayed sound source making interference like sone reflection, resonance or diffraction. The longer the delay the lower in frequency interference is seen in a frequency response plot.
Frequency response of idela transducer would be flat (sans beaming) if it was only direct sound from the transducer. Any deviation from this is due to at least one another delayed sound source making interference like sone reflection, resonance or diffraction. The longer the delay the lower in frequency interference is seen in a frequency response plot.
I addressed diffraction in my latest diy using 2 spheres, one for the mid woofer and one for the tweeter, the mid woofer a 3 in coil and a dome comprising more of the diaphragm, crossed at 100 Hz low (it's pretty flat to 100 Hz) and 2,000 Hz high (12 db) and the tweeter an 1 1/8" dome which goes low and handles high power. So sphere enclosures and avoidance of cones, conventional upper - lower set-up. Low base is via an 8" subwoofer.
People might debate measuring diffraction for overall impact on tonality (but the effect can be "seen" by measuring sound waves emanating from baffles surrounding a driver), interesting video presentation - the meat of the presentation is in the latter 25 mins:
Diffraction can be heard by A-Bing the same set of drivers, one set mounted in more conventional enclosures while other in spheres or, in the case of sealed tweeters or mids, just put them on a small rack almost as if they simply hung in free air. Rounded edges are not enough as diffraction can happen off the sides of enclosures as well.
The plates around the tweeters I used (Daytons) are larger than I would like and can diffract also but best I can do if I want that tweeter. Other tweeters have smaller mounting plates.
Play an instrument through a hole in a baffle (clarinet, etc.) and it will be different in tonality than one played in normal free space.
People might debate measuring diffraction for overall impact on tonality (but the effect can be "seen" by measuring sound waves emanating from baffles surrounding a driver), interesting video presentation - the meat of the presentation is in the latter 25 mins:
Diffraction can be heard by A-Bing the same set of drivers, one set mounted in more conventional enclosures while other in spheres or, in the case of sealed tweeters or mids, just put them on a small rack almost as if they simply hung in free air. Rounded edges are not enough as diffraction can happen off the sides of enclosures as well.
The plates around the tweeters I used (Daytons) are larger than I would like and can diffract also but best I can do if I want that tweeter. Other tweeters have smaller mounting plates.
Play an instrument through a hole in a baffle (clarinet, etc.) and it will be different in tonality than one played in normal free space.
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You seem to be conflating geometric effects with diffraction. Your examples and explanations appear to have the same limitations as the simulator you use.. it was not meant to be a teaching tool.