I'm also not convinced that placing them horizontally would be better, if your objective is wide horizontal dispersion. Anyways, your current sims already give pretty good vertical polars, so cutting down further on CTC doesn't seem necessary
I'm still baffled by the horizontal graphs... the drivers being quite small narrow, I'd expect better results than we see here.
Could you show what a single driver DI looks like, both horizontal and vertical DI graphs? You can change the impedance graph on bottom right to show the DI graph.
Could you show what a single driver DI looks like, both horizontal and vertical DI graphs? You can change the impedance graph on bottom right to show the DI graph.
I return to my initial question. Whether we should simulate oval drivers as circular or rectangular. Due to the format, I simulated them as rectangular but is the rectangular drivers option in the layout tool suitable or optimized only for planar drivers?
I sent this question to Kimmo Saunisto, VituixCAD developer, who promptly responded to me with the following:
"That looks more rectangular than circular. You can also test what happens with three circular radiators with D=39mm - is there any or significant difference to single rectangular of ca. 39x70."
I understood your reasoning. The driver in question has approximately 28cm2 in area. If it were a rectangle, for a width of 39mm, it would be as if the height were 72mm. Vamos testar.
Thank you very much for your attention @kimmosto!!!
"That looks more rectangular than circular. You can also test what happens with three circular radiators with D=39mm - is there any or significant difference to single rectangular of ca. 39x70."
I understood your reasoning. The driver in question has approximately 28cm2 in area. If it were a rectangle, for a width of 39mm, it would be as if the height were 72mm. Vamos testar.
Thank you very much for your attention @kimmosto!!!
Like Bose Panaray speakers, but with drivers mounted offset as I proposed, is that it?
Interesting idea. For now I will exhaust the possibilities with what is possible to simulate in VituixCAD. Very cool tool. Thanks for the tip @wesayso 👍
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25 oval drivers simulated as rectangular measuring 82mm(H) x 39mm(W). Vertical c-t-c = 82mm. Horizontal offset = 51mm.
Can't say I would have predicted something like what you've posted above.
Here's a TC9 array with a shorter center to center distance. (reduced from 85.5 mm(*) to 80 mm):
Compared to an unshaded array with 85.5 mm center to center distance:
Driver layout for the top example:
Based on a quick sketch, I chose a 40 mm distance to keep the effect on horizontal polars to a minimum (or so I thought):
(*) That's what I had available, it's not an actual 85.5 mm distance between the drivers in Vituixcad, it's 85 mm, and the next being 171 mm etc. to come closest to my actual build that was using 85.5 mm. VituixCAD doesn't do half a mm.
Here's a TC9 array with a shorter center to center distance. (reduced from 85.5 mm(*) to 80 mm):
Compared to an unshaded array with 85.5 mm center to center distance:
Driver layout for the top example:
Based on a quick sketch, I chose a 40 mm distance to keep the effect on horizontal polars to a minimum (or so I thought):
(*) That's what I had available, it's not an actual 85.5 mm distance between the drivers in Vituixcad, it's 85 mm, and the next being 171 mm etc. to come closest to my actual build that was using 85.5 mm. VituixCAD doesn't do half a mm.
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The model may be assuming a pistonic driver of the dimensions you input, while the actual driver response is not pistonic- the virtual dimensions change with frequency.
http://www.diyaudio.com/forums/multi-way/236037-dirty-dozen-line-array.html
This is the actual measured horizontal response of a single 2"x 4" (50mm x 100mm) oval driver, horizontal being 100mm left to right:
Your driver's horizontal polar response may be more similar to the response above than the simulation.
As Wesayso already mentioned, the horizontal response of the array will be similar to that of the single driver, though your proposed offset arrangement complicates that..
At any rate, without actual polar response measurements of an individual driver on a baffle, the model won't be as representative of what your end results will be as they could be.
Art
Yes, like the Panaray. For now stay focused! It’s interesting stuff!
I don't have equipment for real measurements to confirm the simulations. At most one RTA smartphone app.
The most accurate information I got was the T/S parameters with the REW, and I only measured two units with similar results.
I'll follow up with what you and @wesayso have already said about the horizontal response of the array being similar to that of the single driver.
As suggested, simulation of 75 drivers divided into 25 groups formed by 3 circular drivers of 39mm each in a total arrangement of 81mm. Ctc=81mm and offset=50mm.
Unfortunately the sims are all going to be useless as the individual drivers vertical and horizontal directivity will be different unlike a round driver. You’d be much better served just getting yourself a measuring mic and a quiet spot outside to see what you’re actually working with.
Even if it were a round driver, a simulation would be different from a measurement. So I don't consider it useless.
Who knows, maybe someone with a microphone and some oval drivers mounted vertically could validate this idea.
Who knows, maybe someone with a microphone and some oval drivers mounted vertically could validate this idea.
I have to agree with @weltersys. In real life most of the top end will come from the dome in the middle and you'd see much different vertical results due to the increased spacing of those domes vs what these simulations show. In all honesty, the horizontal results by themselves should be enough to abandon the idea.
Take a close look at the red line in the middle left graph, showing the Directivity Index. In an ideal world you'd want that line to be as smooth as possible for best results in real rooms. Can't say that I see that happening here. It most probably won't sound balanced and will not be fixed easily with EQ.
Might still be fun to try though (on a budget), as it really seems to light up the room at all frequencies. Just wish it was a bit less unbalanced at ~4K and ~11K.
It would sound pretty lively I guess 😀. Long therm my prediction would be: you're going to battle with the uneven DI curve and never really get a good sounding EQ balance.
Take a close look at the red line in the middle left graph, showing the Directivity Index. In an ideal world you'd want that line to be as smooth as possible for best results in real rooms. Can't say that I see that happening here. It most probably won't sound balanced and will not be fixed easily with EQ.
Might still be fun to try though (on a budget), as it really seems to light up the room at all frequencies. Just wish it was a bit less unbalanced at ~4K and ~11K.
It would sound pretty lively I guess 😀. Long therm my prediction would be: you're going to battle with the uneven DI curve and never really get a good sounding EQ balance.
You could always try making foam core test cabinets
https://www.diyaudio.com/community/threads/foam-core-board-speaker-enclosures.223313/
And if you're pleased with the sound could make real wood ones
https://www.diyaudio.com/community/threads/foam-core-board-speaker-enclosures.223313/
And if you're pleased with the sound could make real wood ones