Curved magnetostatic speaker

[båndsei]

To bend it vertically is a mistake.There is loss of spl. and worse, loss off spl.in low freq.
Butt i vill still bend it horisontally .

Here is a picture of my setup

The sensivity of my planar speaker is higher than of the above.

 

[R. Jamm]

Båndsei, you never gave a description of how these speakers sound? Do they give you a 3-d image? Are they holographic? What do they sound like? What speakers do/would you compare them to?

båndsei, do you make a kit of your project, so that other people can try them?

 

[båndsei]

I like the sound of ribbon speakers,but i want to make a "fullrange" speaker. It dont have to be high end just hifi.I wanted to elliminate the hot spot,and I did that.Now i will make a curved planarspeaker 20X115cm.

Here is a picture of the steel konstruction.

 

[a.wayne]

Bandsei ,

It's interesting to see your attempts , as I'm also playing around with a similar steel construction , the difference being , flat as oppose to curved and push pull for better full range operation ...

 

[jzagaja]

Which glue is good for neos and aluminium? Last night I have used polyurethane with 10kg load. After 24 hours it's still wet! Anyone tried anaerobic glues?

 

[moray james]

loctite black max....

best if you can abrade your neo magnet surface if they are plated.
http://www.henkelna.com/us/content_..._380_Outlasts_Contact_Cement_and_Silicone.pdf

 

[båndsei]

Here is a picture of my newest speaker.

And from behind.The subwoofer has a 15" passive radiator in the bottom,and it seems to be easier to match it with the panel as it is "tilted" 45`
It dosn`t go as deep as my first panel but deeper than my seccond one.This one is wider and not as curved.
I use iron and dont have to glue the magnets,and if i had to,i would`t use too strong glue becourse i will be able to remove them again.You could use silicone but not with accid, use one with alcohol regarding the aluminium.

 

[a.wayne]

Bandsei,

You make hard work look easy .......... the metal work is fantastic looking .

 

[båndsei]

I like the look of my newest planar ,and it is rather easy for me to make metalwork.I have the right tools.But i want it to go deeper,or maybe reduce the output in high frequenses.
Would it helpe to curve the membrane more, and wich radie would be the best??
The speakers from Martin Logan have curved membranes,what radius ,and how wide are they.

 

[a.wayne]

Hello Bandsei,

Getting good bass out of your planer will take some work. Take a look at Magnapan l planers , i really can't see you getting good bass without going hybrid or to a large push/pull planer arrangement ..

 

[tinitus]

Hello Bandsei,

i really can't see you getting good bass without going hybrid

I concluded that also, many ears ago making bigger planars...without knowing anything about the struggle with "ordinary" dynamic drivers

I do think now that it would need to be an array of smaller woofers, working in the low "dipole-loss" frequency from around 300hz and below

And with that the planar could have the benefit of being smaller(narrow)

You can also build a planar sub 😀 http://infraplanar.free.fr/

edit, note also that when you curve the design like that, you "support" the diaphragm at many points, so that it is actually devided into many smaller ones, with higher ressonance, hence less bass

My guess is that it would be better to curve it only vertically, but which way, forwards or opposite, I dont know 🙄 but I do have a suspicion 😉

Or you could split it up in 3 sections, each horisontally curved, but mounted "curved" vertically the opposite way

 

[jzagaja]

Jamesbos claims his planar goes fullrange. What about bipoles, infinite baffles should help?

 

[båndsei]

My aim is frekvensresponse to 100 hz.I know i need a sub.I think you are right about the width,it might be smaller,my first type was 12cm.x96cm. and was curved at R.31 cm The new one ,the third,is wider , 20cm.x113cm. and curved at R.36.The idea with 3 panels I cant visualice it right now ,i will have to think more.

 

[a.wayne]

Tinitus,

Yes i do plan to build a push /pull planer bass/sub driver 😀 tall as oppose to being as wide as the one shown ...

 

[tinitus]

Hi Wayne, sounds good and hope we will see it some day, real heavy stuff ... I admit I like the wide one 😎

Båndsei

I imagine a 3 segment something like this...not sure if 1 or 3 segment tweeter

If you want it down to 100hz you either need equalising, or a 2way design...I dont think theres any other way around it

 

[a.wayne]

Hello Tinitus,

Still working on it .........................................................

 

[Ed Holland]

I love the infraplanar in the link supplied by tinitus. It would be fun to build something similar. After looking closely at the construction of my Magnepan's, I'd previously wondered about constructing something using a similar distributed drive principle, but with a rigid "piston" in place of a stretched diaphragm. It seems Infraplanar were ahead of me 🙂

Also, I have to say that I admire the elegant work exhibited by båndsei and others in this thread. Great stuff!

Cheers,

Ed

 

[jzagaja]

best if you can abrade your neo magnet surface if they are plated. http://www.henkelna.com/us/content_...nd_Silicone.pdf

Abrasion doesn't help. Have tried all glues from hardware store. Is Loctite so magical?

 

[moray james]

Magic no...

Well suited to your alpplication yes. Black Max is a very popular speaker magnet assembly adhesive, also used to bond disk break pads amongst other uses. Get the accelerator as well ro make for a stronger and faster joint. A rough surface is always better than a smooth surface as it will provide additional surface area for the adhesive to get a grip on to. Check with Loctite for additional information.

 

[båndsei]

Here is my latest speaker.

It is 12x96 cm.curved plannar,and 3 ribbon tweeter.The sub. is 12" with passive radiator.I have not had the time to finish the filters so i play only with the plannar.In this model  i only use 4x12 magnets 48 pc. The sensivity is almost the same as in my first model where i used 6x12 magnets 72 pc.