The making of: The Two Towers (a 25 driver Full Range line array)

The question I'm asking myself is not about the Z itself but how the SPL from each group and individual drivers changes as a result of the Z mismatch, which gets pretty large above 200 Hz. If I hazarded a guess it would be just that.

If you made up a separate driver model for each driver with the only thing differing among models being the Z curve, you could simulate it in Vituix, if Vituix does take that into account. . My fear is that the amplifier drive current divides among the 5 groups according to the relative Z's of the groups and that you might have to add some equalizing Z components to get equal output per group pre shading.
 
Not sure I follow you... these groups have the shading active, and don't seem to deviate all that much between each of the 5 drivers within a group.
Most important group is the unfiltered (red) 5 drivers, so I made sure those are the closest group.
The rest of the groups all have resistance in their path from the filters used...
 
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The last one you add will dominate the graph, but here are the groups unfiltered:
temp-unfiltered.jpg


As can be seen, the black drivers dominate the top end, the added resistance (the most resistance is used in the black group of all groups) will push them down again in final situation with filters.
The red is basically the same as in prior graphs, the other colors hardly show at all. So I'd say it's looking pretty even without any additional help?
Did i miss what you meant here? :)

Here's the current graph per driver, pré filters. Again with 100 watt input into 8 ohm:
temp-unfiltered-current.jpg


And the current per driver when shaded:
current per driver-shaded.jpg


Looks as expected. As the power distribution Vituixcad showed us.

25x 10F FR Shaded 19.0 as build-notches-ABEC-minphase-20dB Filter.png


Am I missing your point entirely? :D
 
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After cutting several frames of the 10F's I am pleased to say the cutting jig works out well.
Nice and precise cuts and very good repeatability.
It's still a lot of work, but I've never been bothered by that. It gives me time to contemplate.
Still lots more to go but by just keeping at it, it will be done some day. (It's making me zen :D)
I'm taking my time, the weather isn't even nice enough to consider moving the arrays out to
the garage. So for now it's headphones to get a dose of good music. And hopefully soon some
live concerts to go to again, it has been a while.
 
I'm about half way trough. I started about a week ago tomorrow, so that's going quite smooth.
.....but if the weather permits...
I was wondering... no news, and no reply to my pm. I was getting worried.
So, just slowly busy. Ok!

Weather here has turned for what seems to follow last year's winter, our worst winter ever over here. Not fun.
Wish you much better !
 
Finished cutting driver frames yesterday. 50 of them, ready for use. Now hoping for good weather so I can drag the arrays inside, one after the other, to
slightly change 3 of the shading boards and remove the TC9's. Clean up the baffle (again) from the use of butyl, add the new drivers (by number) and
close it all up again. All of this at a snail pace ;). :snail:
 
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Just a hair under 84 mm, I aimed for the same size as the TC9 FD18-08 it replaces.
That one is quoted as 83.75mm which sounds about right. One of my samples measured about 83,8 mm (probably +/- 0.5 0.3 mm).

A jig helps to make it repeatable...
template-lock.jpg


The edge of the surround is slightly wider on the 10F, which means there is next to nothing left of it where the cut is...

deux.jpg
 
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