Full range planar speaker using neo magnets

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The bass of the Apogees is much better than the Magnelanars, stronger magnets would increase the sensitivity or one can use smaller Neo magnets.
What are typical sizes of the Pastiform magnets?

This is a picture of the Magnepan Tympani bass panel.
The magnets are about 8-9 mm wide.
The magnets for the tweeter/midrange is like the other picture.
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Sorry for the ignorance but how do you determine how low one of these designs can go?

I dont know anything about these types of speakers. I was looking at maybe doing a very tall ribbon tweeter but now am starting to wonder about these for my next build.

Only thing close to this I have ever heard is a ESL speaker from Martin Logan. How is the back wave controlled on these types of speakers?

I have restrictions in the size I can build but 22" wide x 48" tall is about as big as I want to go. If thinner than I can go taller but just have to learn what does what according to size.
 
The bass of the Apogees is much better than the Magnelanars, stronger magnets would increase the sensitivity or one can use smaller Neo magnets.
What are typical sizes of the Pastiform magnets?

Just remember that stronger magnets can kill the wanted high Q in the bass. It is not very easy to end up with both high efficiency and good bass extension. Using Neodynium magnets allows you to use smaller magnets but it will be expensive.

The Plastiform magnets used by Magnepan for most bass drivers measures: 1/4 x 1/16 x 55 inches.

Why not just use B&G Neo 8 ribbon driver or Neo 10 driver instead of DIY?

If you want to replace pair of Magneplanar mid and tweter, you will need 12 pieces of Neo10 and 32 of Neo3-PDRW in order to reproduce the frequencies ~150 Hz and upwards. It will cost about $3500. You can buy a pair of used Magenpan MG 3.6 for that kind of money and they will go from ~35 Hz and upwards.
 
Hi...
This topic about planar speakers are cool and interesting.
So what i have in plan...
Just for testing purpose i want build small planar with one neo magnet
from hard disk.
Is this magnet quite good for small speaker ,for example 10x10 cm..?
when i read this topic i see that is for good sensitivity i must have covered
whole back surface with magnetic field,right?
So i have in plan put this magnet on iron net .
What you think about that.
For membrane i plan to use water proof folium for floors and add cooper
wires on this folium.

Any suggestion will be great...
cheers!
 
You will find all you need in my photos Rubendev, I wouldn't use copper wire but aluminium tape you can cut this to different widths the smaller the better and I would also use 6um mylar A. This is best for sensitivity. The lighter the membrane the better. I use 50 x 12.7 x 3mm neo magnets any larger ones are too dangerous, especially if you use a lot like I do. I am in the process of building my latest design. 4' X 2' using 816 magnets in 6 columns of68 magnets on each speaker, I am also using 6um mylar A for the diaphragm and 2.25 mm wide aluminium tape cut by hand as I don't think you can buy aluminium tape this wide!! when I am satisfied with latest design I will upload some more pictures. Wish me luck!
 
not really especially compared to ESL speakers. I have no problems using valve amps of low output. The only problem I have is trying to get my new 9.2 ONKYO Amp set up properly! There are so many different settings, I think it will take the rest of my life to really sort it out. I am too busy at the moment. With my latest rebuild and cutting the foil into 2.25 mm strips, I'm also in the process of designing and building full range planar headphones, so have quite a bit to do. If my rebuilds using the thinner tape and mylar are successful, I may have to rebuild my rebuilds, so I have plenty to keep me active. I only hope I've got enough energy to carry on.
 
Yes,That will work what are you going to use as your etchant masking?

I have some of the same material and have thinking about this as well for quite some time.
I am just wondering about the resistance of some thin strips.
I have some 3/16" wide stuff ,also, and it is on the order of 200 ohms per foot.
If I remember correctly the sheet stuff I have is much much less like practically no resistance when I run across it I will measure it again.

When I get some time I am going to try the toner transfer method and etch some Aluminium foil then glue it to some mylar.
I think that this might work well for some small drivers.

jer :)
 
I have just built a 60 x 40 cm sized speaker weighing about 8 kilos, which is more sensitive than a 4' x 2' one using 294 40 x 18 x 10 mm ferrites. The bigger one used the epsilon design i.e. gaps between the magnets, difficult to glue down, easy to dislodge!! I speak from experience. My new design using the same magnets only 125, and no gaps between the magnets is more sensitive than the bigger one. You live and learn!
 
LATEST DESIGN

USING MY 6 MM MAGNETS AS THE DESIGN BEFORE WAS DISAPPOINTING :-Will be doing diaphragm tomorrow based on the epsilon design.. Have managed to draw it , after 2 mistakes, certainly going senile. But I always get there in the end.
 

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