I don't know what You're seeking.
When I simulate the actual circuit in Basta, I get results that pretty much correlate with my impedance measurements.....
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Ahh, the problem is solved!
With "direct drive" I mean driving the ribbon without transformer! (with or without cross over as specified)
With "transformer drive" I mean driving the ribbon with transformer! (with or without cross over as specified)
The graphs in post#151 are taken with cross overs connected.
With "direct drive" I mean driving the ribbon without transformer! (with or without cross over as specified)
With "transformer drive" I mean driving the ribbon with transformer! (with or without cross over as specified)
The graphs in post#151 are taken with cross overs connected.
If you read post#151, you can see in the text that the two measurements are taken of complete speaker, with bass driver and then also of course the cross over (filter) included in both post#151 graphs...
Again, I just wanted to show the different impedance characteristics of the two drive methods..
Placing the filter after the transformer would have been a novelty way in ribbon transformer design, or at least (to me) nearly unheard of.
Is it even possible, considering core saturation and such?
Designing my 6 inch ribbon tweeter 
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Thanks
Quite straight forward, by determine the actual conducting plane that you are going to run to both ends of the alu ribbon. Which in my case I use copper foil stickers.
Once you determine your length of the conducting plane(Copper), run a alu ribbon which is the actual size, thickness and corrugation ratio you going to use. The Alu ribbon will act as your real load when you determine the number of coils in your primary coil. Without any magnets, use Woofer Tester 3 to run a quick sweep on the transformer to measure the impedance.
The reason for this is to include the DCR of the copper foil sticker(Conducting plane), to give you the real total load(Conducting plane + Alu Ribbon). Due the low DCR of the alu ribbon, any slight changes on the conducting plane will mess up your impedance seen on the primary coil.
For secondary, I use 5 pieces of magnet wires running 5 rounds on the bobbin which I feel its more than enough bandwidth.
A WT3 will be very useful.
Dayton Audio WT3 Woofer Tester
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You can the copper conducting plane, which runs all the way round the side to the inner bottom of the yoke.
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Its the same transformer I used for my 2 inch ribbon, EI core
My old 2 inch ribbon transformer
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My old 2 inch ribbon transformer
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almost one turn of .3 mm insulated copper sheet directly laid on the oriented iron core. And 20-30-40 turns of prim...
But nowadays I drive my one meter ribbon without transformer, instead I use a 100 uf very high quality film cap and a 3 ohm metal film resistor in series with ribbon.
Does it sound better without transformer? Well, the music is more HD, but I'm not sure
about musicality... It's like some older films on TV, it's more pleasant to watch with less pixel density.....
By the way, ghemml, I dont know if you're using oriented iron, but if you dont, try to get some! Big difference in the highest treble...
But nowadays I drive my one meter ribbon without transformer, instead I use a 100 uf very high quality film cap and a 3 ohm metal film resistor in series with ribbon.
Does it sound better without transformer? Well, the music is more HD, but I'm not sure
about musicality... It's like some older films on TV, it's more pleasant to watch with less pixel density.....
By the way, ghemml, I dont know if you're using oriented iron, but if you dont, try to get some! Big difference in the highest treble...
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@JonasKarud
I believe there is less coloration on the output on your tweeter if there is no transformer. Its more workable on large ribbon like yours, mine will just cause overloading on my amp in which I burn and destroyed my LM3886 while performing some test.
Though I'm a Chinese but I'm not from China, so its been quite difficult for me to find parts from places like Taobao.com because my ability to read Chinese is ultra poor... LOL. I only managed to find ferrite cores when I was having a tour in China's Shenzhen and Guangzhou.
For my transformer I bought from Korea, its a 49% Nickel Permalloy, and there are 3 sizes to them. You can drop me a PM if you are interested.
I believe there is less coloration on the output on your tweeter if there is no transformer. Its more workable on large ribbon like yours, mine will just cause overloading on my amp in which I burn and destroyed my LM3886 while performing some test.
Though I'm a Chinese but I'm not from China, so its been quite difficult for me to find parts from places like Taobao.com because my ability to read Chinese is ultra poor... LOL. I only managed to find ferrite cores when I was having a tour in China's Shenzhen and Guangzhou.
For my transformer I bought from Korea, its a 49% Nickel Permalloy, and there are 3 sizes to them. You can drop me a PM if you are interested.
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Some quick measurements, haven't had the time to do polar measurements but will perform one polar test and post up soon
Freq Response
Distortion Level(%)
Freq Response
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Distortion Level(%)
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