I've had a few Yamahas in my day and from my experiance they never sound good right out of the box. There have been many discussions on how to "make the drums come alive" by applying the proper eq. The Tyros I had needed many adjustments. OTS voices were drowned out by too much arranger, drums too soft and so on. To me it seemed like it needed a lot of balancing and it was rushed to market too fast.

In Yamaha's defence, they give you the tools needed to make it sound good, you just need to use them.

Tom