Originally Posted by
davef
Hi Audiohead!
Correct, presently the RAAL ribbon upgrade for the towers is $700. This is likely going to increase fairly soon.
RAAL True Ribbons have nearly zero stored energy and a more accurate transient response. They are actually quite a bit LESS directional than dome tweeters in the horizontal plane, meaning they have wider and more linear horizontal dispersion (this is a critical performance factor). They are more directional in the vertical plane which helps reduce both floor and ceiling reflections which leads to greater clarity.
Hope this helps!