Diy AMT

[Thomas Spilcker]

It' s PERFEKT !

 

[zmyrna]

Bandsei,
Thank you for posting your project here.
I have been using an Oskar Heil Syrinx for nearing 10 years now.
And lately, I have been experimenting with BG neo drivers on full open baffle projects.
I have already made a dipole waveguide for a neo3, very similar to yours in design and materials.
My next project is a similar WG for a neo8s (drivers in the post).
Your DIY AMT has similar height to a neo8? What is your view on your driver's vertical dispersion and effects on listening experience?
I am hoping to be able to use the neo8s without any tweeter or supertweeter on top.
To increase the vertical dispersion, I will experiment with felt and foam covering 1/3 upper and 1/3 lower parts of the radiating surface of neo8. Just like Raal does with their taller ribbons.
You seem to have much better skill, knowledge and equipment to test this idea.
Would you give it a go?

 

[båndsei]

zmyrna
Sorry for my late answer.
My AMT´s are 170x40mm,active app.150x32mm.
Vertical dispersion is like line source,not good.I plan to make another model with the AMT´s horisontal.
A shorter diaphragm acts maybe more like a point source.
I will be eksperimenting with vertical dispertion.

Bernt

 

[SEdwards]

Have you considered just exposing less of the diaphragm to a horn?

It might be good to have the glued ends where displacement cannot be as linear removed from the output. Maybe you'll still have enough output.

 

[båndsei]

It might work,like a shorter AMTwould.
But i like my own idea,and have not seen this idea used.Could be fun.
I have made someting similar:

This one is with 5 ribbon and vertical.
The new idea is horisontal with 3 AMT´s.

Bernt

 

[båndsei]

I have anounced that I would show how to make my frames.

[URL="http://img585.imageshack.us/img585/8206/80mmrammemembran007.jpg
[IMG][URL=http://img339.imageshack.us/i/80mmrammemembran008.jpg/][IMGDEAD]http://img339.imageshack.us/img339/3711/80mmrammemembran008.jpg[/IMGDEAD][/URL]


I use hard wood and normal glue for wood.

Bernt

 

[båndsei]

This is the curved model:

I only have 2 diaphragms yet.
More later

Bernt

 

[Thomas Spilcker]

Have you seen that ? It shut be a old german produkt.

 

[båndsei]

Hmmmm.
Never seen this before.Is it a ribbon with a kind of horn?
Not sure it is manufactored to be a speaker.May be a mix of stuff.

Bernt

 

[Thomas Spilcker]

www.igdh.eu ( Interessegemeinschaft DIY.) Frickelfest 2009.

 

[tinitus]

.....should be a old german produkt.

ahh...looks to me like it could a half 'Rubanoide'

 

[Thomas Spilcker]

Linaeum hôgtoner.de ?

 

[tinitus]

yes, I think you are right..Lineum might be the original, and right generic term

but it is not AMT
there is another thread about it

http://www.diyaudio.com/forums/planars-exotics/69450-diy-ribbon-speaker-different-kind.html

 

[bsyoon]

magnet system

I don't know why nobody try to test U-shape magnet system of MUNDORF.
Here is the result of mine.
Please point it out if something wrongs are there.

 

[solhaga]

I´m not familiar of the Mundorf system. Could you explain for example what´s magnetes and what´s pole pieces?

The field looks strong and even. Could you simulate b.t and b.n separately?

 

[båndsei]

I would like to see the femm.drawing too,and as solhaga wrote,it looks good.
I prefer the open model I use myself,but this one has stronger and more homogen field.

Bernt

 

[bsyoon]

I´m not familiar of the Mundorf system. Could you explain for example what´s magnetes and what´s pole pieces?

The field looks strong and even. Could you simulate b.t and b.n separately?

Attached my magnet system in detail.
There are 6 magnets of 40x25X10mm, N35 and the inner steels are separated each other to be attached on the magnets perfectly.
The gap between the inner steels doesn't affect to the flux density so much.

 

[solhaga]

Just did a simulation of a much slimmer design of my AMT with an air gap of only 40 mm.
I get the same b.n strength as yours but even in the whole gap 0 - 40 mm.
The b.t field is zero in the whole gap 0 - 40 mm.

It is also much easier to make with straight rods everywhere.

 

[bsyoon]

Just did a simulation of a much slimmer design of my AMT with an air gap of only 40 mm.
I get the same b.n strength as yours but even in the whole gap 0 - 40 mm.
The b.t field is zero in the whole gap 0 - 40 mm.

It is also much easier to make with straight rods everywhere.

Thanks for your reply !
Truly, the U-shaped magnet structure is not so simple to make.
I'd like to see your simulation.
Could you introduce your slimmer design ?

 

[solhaga]

Small AMT

"Could you introduce your slimmer design ?"

Here you go.