Despite my lack of indepth knowledge, i started out creating a list...


Seems the SD9PRO has everything the SD7 has except for
-Speakers
-Joystick (replaced by wheels)

On top of that the SD9PRO offers
-76 keys
-150 more sounds
-more drum kits extended drum set edditing
-700MB for user samples and sounds
-Live guitar riffs
-launchpad

while the Audya misses the nigty interface and some of the newer features as a player and the launchpad, and only max 256MB for user samples and no multi audio track player. it also has some things to offer not on the SD9Pro
-192 note polyphony vs 128
-not only drum and guitar, but also Bass, synth, pinao, percusion and more types of audio tracks..
-more external pro connections like sepperate audio outs and spdif
-real drawbar organ simulation
-full drawbar sliders


And the Ajamsonic adds to that
-VCE2 voices
-Huge amounts of content (sounds, styles, live drums and guitars)
-Arpeggio´s


There is probably a huge amount of things i forgot about, please feel free to add to this list...