yes you would have to make smaller traces say 2 mm and use 5 traces. now ur coil is 5 times longer, so not 5 meter but 25 meter. resitsance will be 25 ohm with the same thicknes. BUT we decreased the width from 20 to 2 as well so resistance goes up 10 fold. hmmm 250 Ohm ? with 0.00143 thickness.
250/5=50 so if we make the alu 50 times thicker we are back at 5 Ohm
50*0.00143= 0.071
71 Micron alu. is needed. now we got a mm2 of 0.070*2mm = 0,142
well 70 micron is rather thick, this might be to thick for a mid/tweeter
well play with it a bit i suggest, i suggest making less turns decrease the 25 meter to around 11, and use 30 micron foil. to make you own laminate
Dik aluminiumfolie Zelfklevend | Aluminiumfolie.nl
because finding a good laminate is hard, believe me i looked for years now since i wanted to etch one to. it either comes in rolls of several Km or not at all.
i asked this alumnium shop guy for a small sample wich he did not send ofcourse. so you might have to buy a complete roll
.
cheaper way is calculate everything back to household foil. 10 micron thickness. or the more expensive thicker ones. (in the AH there is one brand i believe that mentions the thickness)
layout the foil on a wetted glas plate with kitchen soap. remove all bubbles clean and spray glue on it. do the same for the foil on antoher plate , combine the to and be sure to remove all bubles.
If you can find it a danish guy that made huge ribbons used this method.
only problem might be etching , i dont know if the glue will hold.
250/5=50 so if we make the alu 50 times thicker we are back at 5 Ohm
50*0.00143= 0.071
71 Micron alu. is needed. now we got a mm2 of 0.070*2mm = 0,142
well 70 micron is rather thick, this might be to thick for a mid/tweeter
well play with it a bit i suggest, i suggest making less turns decrease the 25 meter to around 11, and use 30 micron foil. to make you own laminate
Dik aluminiumfolie Zelfklevend | Aluminiumfolie.nl
because finding a good laminate is hard, believe me i looked for years now since i wanted to etch one to. it either comes in rolls of several Km or not at all.
i asked this alumnium shop guy for a small sample wich he did not send ofcourse. so you might have to buy a complete roll
.cheaper way is calculate everything back to household foil. 10 micron thickness. or the more expensive thicker ones. (in the AH there is one brand i believe that mentions the thickness)
layout the foil on a wetted glas plate with kitchen soap. remove all bubbles clean and spray glue on it. do the same for the foil on antoher plate , combine the to and be sure to remove all bubles.
If you can find it a danish guy that made huge ribbons used this method.
only problem might be etching , i dont know if the glue will hold.
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How much amps will that withstand or what size do I need for about 200 Watt?
well 70 micron is rather thick, this might be to thick for a mid/tweeter
well play with it a bit i suggest, i suggest making less turns decrease the 25 meter to around 11, and use 30 micron foil. to make you own laminate
Dik aluminiumfolie Zelfklevend | Aluminiumfolie.nl
because finding a good laminate is hard, believe me i looked for years now since i wanted to etch one to. it either comes in rolls of several Km or not at all.
i asked this alumnium shop guy for a small sample wich he did not send ofcourse. so you might have to buy a complete roll
cheaper way is calculate everything back to household foil. 10 micron thickness. or the more expensive thicker ones. (in the AH there is one brand i believe that mentions the thickness)
layout the foil on a wetted glas plate with kitchen soap. remove all bubbles clean and spray glue on it. do the same for the foil on antoher plate , combine the to and be sure to remove all bubles.
If you can find it a danish guy that made huge ribbons used this method.
only problem might be etching , i dont know if the glue will hold.
I don't expect it to become a real tweeter so in time I will add one (ribbon?) anyway.
Now I first want an amazing sounding wide range squawker.
I don't want to hassle with soap thin layers of foil, conductor material and whatnot.
It must be possible to have it done by a specialized company under clean conditions in a way that the conductor layout can be etched. Withing limits, I am willing to spent a few bucks for that.
Also for the etching, it should be nice if I can find a company which can do that for me.
I can make a layout in any form for them to print or laser it. So if I can get my hands on a conductor on a (kapton?? ) foil, the etching will be possible too.
First things first, now that I have a good idea about the magnet layout and how to adjust the impedance, I need the know what size conductor cross section I need so that it can handle a decent amount of power. I do know that the old maggies can handle power until the membrane hit the magnets and if I my memory serves me well, the wiring for that “low/mid” part was a a lot
bigger then the 0.142mm^2 in your calculation.
So far I haven't found what conductor size is needed for how much power/ampere.
Help is appreciated
You mention FEMM for a simulation, I don't know what that is but if you have it or have used it….....
Edmund
Hi James,
I am still very interested, did quite some reading about the subject and appreciate your input here.
My experience with planars is that they are very directional and they have other shortcomings as well, so if “we” can improve that I will be happy.
Unfortunately I don't have the time or desire to go 24/7 studying all option and I would appreciate if someone here could do a little FEMM simulation for me.
I do have a quite detailed plan on how I want to build my planars and to make it as (cost) effective as possible I need to know what kind of perforated plates are available along with what kind of NEO magnets
( dimensions ).
I want to fit it in a way that I have way more open space compared to what you use.
In respect to all your good work, I doubt very much if simple planars frequency response even comes close to 20 -20kHz. 20 Hz is pretty much impossible with an open planar.
My main objective will be an outstanding wide range squawker, if it does highs too, even better.
For the lows I plan a conventional speaker.
I am still very interested, did quite some reading about the subject and appreciate your input here.
My experience with planars is that they are very directional and they have other shortcomings as well, so if “we” can improve that I will be happy.
Unfortunately I don't have the time or desire to go 24/7 studying all option and I would appreciate if someone here could do a little FEMM simulation for me.
I do have a quite detailed plan on how I want to build my planars and to make it as (cost) effective as possible I need to know what kind of perforated plates are available along with what kind of NEO magnets
( dimensions ).
I want to fit it in a way that I have way more open space compared to what you use.
In respect to all your good work, I doubt very much if simple planars frequency response even comes close to 20 -20kHz. 20 Hz is pretty much impossible with an open planar.
My main objective will be an outstanding wide range squawker, if it does highs too, even better.
For the lows I plan a conventional speaker.
neo planars
I buy all my neos and ferrites from China, these are the cheapest available to me anyway as I buy in the 1,000's anyway! You can ask for a quote for any size magnet at this email address! helen@ndmagnets.com They will make any size you need and send them to you, may take a few weeks, even longer over the Chinese new year which is now.I have just ordered 2,000 neos size 25 x 6 x 3 mm. For 318 pounds. Another company would have charged nearly 3 times as much! The 318 pounds included the postage as well! Will be building my latest design using these magnets-size 24 x 16 inches This is my latest full range design, no crossover or resistors required anymore. Still learning with my designs, just a few details to sort out and improve as I have been doing over the last 17 years since I retired!
I buy all my neos and ferrites from China, these are the cheapest available to me anyway as I buy in the 1,000's anyway! You can ask for a quote for any size magnet at this email address! helen@ndmagnets.com They will make any size you need and send them to you, may take a few weeks, even longer over the Chinese new year which is now.I have just ordered 2,000 neos size 25 x 6 x 3 mm. For 318 pounds. Another company would have charged nearly 3 times as much! The 318 pounds included the postage as well! Will be building my latest design using these magnets-size 24 x 16 inches This is my latest full range design, no crossover or resistors required anymore. Still learning with my designs, just a few details to sort out and improve as I have been doing over the last 17 years since I retired!
Hi Henry,
Thank you for the address and sorry for calling you James
25 X 6 X 3 mm seems a usable size to me, now if only one of the FEMM experts here could show me what size, or better : width/ thickness relation of the magnets is optimal for a situation in which the space between the magnets is the same as the width of the magnets.... ( I want more open space )
I suppose the price of the magnets is proportional to the weight of the magnets so the optimal width/ thickness is the most cost effective too.
If a FEMM expert show me the magnets have to be -slightly- closer for an overall better result I like to to know that too.
Anyone?
Next thing is finding a perforated week iron? sheet that meets the dimensions of the required magnets in order to prevent blocking the open area of the metal sheet with magnets.
Help and suggestions are appreciated.
Edmund
Thank you for the address and sorry for calling you James
25 X 6 X 3 mm seems a usable size to me, now if only one of the FEMM experts here could show me what size, or better : width/ thickness relation of the magnets is optimal for a situation in which the space between the magnets is the same as the width of the magnets.... ( I want more open space )
I suppose the price of the magnets is proportional to the weight of the magnets so the optimal width/ thickness is the most cost effective too.
If a FEMM expert show me the magnets have to be -slightly- closer for an overall better result I like to to know that too.
Anyone?
Next thing is finding a perforated week iron? sheet that meets the dimensions of the required magnets in order to prevent blocking the open area of the metal sheet with magnets.
Help and suggestions are appreciated.
Edmund
I don't leave any gaps between the magnets, tried it once made no difference and was more difficult to build, also easily came unstuck. It is better to have the magnetic field without gaps. Is more sensitive this way. I get my perforated steel sheets from RS COMPONENTS. size 1000 mm x 500 mm x.7 mm 4.8 mm hole. They do sell a sheet 500 x 500 mm as well, different sized holes are also available, and different thicknesses.
Hi Henry,
Thank you for the address and sorry for calling you James
25 X 6 X 3 mm seems a usable size to me, now if only one of the FEMM experts here could show me what size, or better : width/ thickness relation of the magnets is optimal for a situation in which the space between the magnets is the same as the width of the magnets.... ( I want more open space )
I suppose the price of the magnets is proportional to the weight of the magnets so the optimal width/ thickness is the most cost effective too.
If a FEMM expert show me the magnets have to be -slightly- closer for an overall better result I like to to know that too.
Anyone?
Next thing is finding a perforated week iron? sheet that meets the dimensions of the required magnets in order to prevent blocking the open area of the metal sheet with magnets.
Help and suggestions are appreciated.
Edmund
any progress ? by the way there is a how to use femm somewhere on the forum. try it it is not that hard, and if you got any question regarding femm and a simple model ,shooot
Best music to tune planars
Great thread, Henry.
What a find to see this wealth of experience in one place.
I have done 2m tall alu-on-foil 25..50mm wide "ribbons" some time ago and can recommend two records for checking on these resonances. Both are, to my ears, beautiful music, too. They share a very direct recording of the main instrument, Christoph Haberer's Mir was, Dir was (Jazzhaus Musik, Köln) and Gary Burton/Chick Corea's Crystal Silence (ECM München). Vibes and closer/farther relatives of that instrument will reveal breakups quite easily. I went on the Infinity Reference Roadshow with the Haberer vinyl way back when and was kicked out by the presenter. Today i believe he was perhaps right doing that as i knew with so many slightly differently tuned EMIM drivers one simply had to go into WARP on playing it
Great thread, Henry.
What a find to see this wealth of experience in one place.
I have done 2m tall alu-on-foil 25..50mm wide "ribbons" some time ago and can recommend two records for checking on these resonances. Both are, to my ears, beautiful music, too. They share a very direct recording of the main instrument, Christoph Haberer's Mir was, Dir was (Jazzhaus Musik, Köln) and Gary Burton/Chick Corea's Crystal Silence (ECM München). Vibes and closer/farther relatives of that instrument will reveal breakups quite easily. I went on the Infinity Reference Roadshow with the Haberer vinyl way back when and was kicked out by the presenter. Today i believe he was perhaps right doing that as i knew with so many slightly differently tuned EMIM drivers one simply had to go into WARP on playing it
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Unfortunately no progress at all. Too busy to invent everything by myself and found very conflicting answers to my questions here.
I hoped that some Femm expert here could help me out but so far, no luck.
For starters I have pretty essential questions that -I would think- everyone needs to be answered and I am a little surprised I did not find the answer here.
Edmund
well use femm. or lookup the method up to use femm. and yes smaller gap means higher field hence higher output. but putting them against each other like james,is not preferred to be honest. you want it to be as open as possible, and at the same time has as much mylar covered with coil, and the strongest field possible.
Well this are NOT my questions and your summery bypasses a lot of options, which is why working together with an FEMM expert would be extremely helpful. In return I am happy to help with some CAD work or post a design here for others to use or buying magnets together with someone since the minimal order is around 1000 pieces. Studying yet again another ( femm ) software package is not really what I am looking for. Unfortunately for an efficient design I need some answers first. Hopefully in a few months I can lay my hands on a power supply and test a few things I need to know.
Then missed the questions you did have
feel free to contact me , I can sum a planar motor , from the magnetics point not the electrical one. (The coil) and I got some experience with etching membranes etc- Status
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