I'm looking to learn about Air Motion Transformer technology

As many are aware, ELAC purchased Oscar Heils' AMT tweeter patent
in 1993, and took it much further with design upgrades that has resulted
IMO the finest tweeter on the planet. Their current jet 5 tweeter is killer.
During the past six months, while recovering from a massive heart attack,
I spent well over a hundred hours listening to HD videos on Youtube of 
the best high end speakers using my Koss Pro headphones on my HP computer with the Altec Lansing processor. I came to the conclusion
after listening to the ELAC FS series with the jet 5 tweeter, that it is the smoothest, richest tweeter I have ever heard during the past thirty years.
I test a tweeter with three musical instruments only, the violin, the piano, and the trumpet. Especially the violin where the jet 5 really shines resulting in the richest, smoothest and most natural tonal character I have ever heard to date through a tweeter and true music lover's of Classical and Jazz who own ELAC's with the AMT jet 5 know exactly what I'm talking about and would agree with my conclusion.

Most on here will most likely disagree with me about amt vs ribbon tweeters.  They do have separate patents, but that doesn't dismiss the FACT that they are different applications on a similar design.  
An AMT is a ribbon that has been folded.  This can change frequency, dispersion patterns etc,  but none the less dissect them both and you will find that a Air Motion Transformer is in fact a folded ribbon.
 Like a horn or dome or any design,  there are many variations and most sound different from one another.  To directly answer your question,  they are fast, typically fairly smooth, often, but not always have a rise on the top end.  Used properly,  AMT's are normally a very satisfying driver to listen to.  Like Ribbons,  you will find some excellent examples and some that can make your ears bleed.  So Not all are created equal,  good luck, Tim    

An AMT is not a ribbon.

In a ribbon the moving part is entirely conductive, and very low impedance so much that they usually require a matching transformer.

In an AMT the conductor is longer, much thinner and attached to a moving membrane which provides the actual moving surface area.  As a result the impedance is much more reasonable.

Further, AMT's have amazing power handling and linearity and lower distortion than most ribbons which tend to be delicate diva's by comparison.

Buy what you'd like!! :)

Best,

Erik

Any way you look at it, the transducer on amt is a ribbon that is folded.