Gilbert,

The onboard (attachable) speakers are quite limited in power, therefore they would not be suitable for providing sufficient audio power to an audience in a large hall where people are talking. Therefore, it appears as if the keyboard(s) have been connected to a substantially larger sound system in order to reach the masses.

I watched all the above YouTube videos, all of which appeared to be recorded by various individuals in the audiences using hand-held video systems with shotgun mics. You could clearly hear people talking in the background while Michael was providing the demos.

Overall, I have been very impressed with the T4 and its features. It, obviously, has more features than anyone on this, and most forums, will ever utilize. Will I be purchasing one? Not at this point. Maybe sometime in the future, when I can no longer physically endure lugging my gear to several hundred performances a year.

Michael Voncken is incredibly talented. He is second to none when it comes to playing ability and knowing the inner workings of the keyboard(s) he plays. Additionally, he has an excellent voice and when recorded professionally, his overall performances are riveting. Several years ago, when I saw some earlier demonstrations, he appeared to be somewhat nervous. His playing and presentations were a bit dry and almost boring. However, they were still very informative. Today, his presentations can be categorized as outstanding. Not only are they quite informative, but additionally, his wit and dry humor make them interesting to watch. If you didn't learn anything from his recent demos I suspect you had some sort of Axe to grind.

Keep those links coming guys and gals--I love watching them all--even if they're not Yamaha.

Cheers,

Gary