Excerpts from page 80 of the Yamaha Tyros Manual.
"These specially programmed voices are not indicated amoung the VOICE buttons on the panel. In fact, they are not even intended to be played from the TYROS keyboard. The MEGA VOICES are primarily intended to be used with recorded MIDI sequence data (such as songs and styles)...........Because of the complex nature of these voices and the precise velocities needed to play the sounds, they're not intended for playing from the keyboard."
With up to eight different sounds for one voice, each with a specific velocity range, playing the mega voices would be next to impossible to do proficiently from the keyboard. SO MUCH FOR LIVE PERFORMANCE.
Be aware I am not stating an opinion, rather reiterating what may or may not be an accurate TYROS manual.
As for me, I'm keeping the nine!
Regards,
Dennis Almond