Hi Dnj,
More than likely the Yamaha Tyros2 has a watered down version of the Yamaha C7 Concert Grand sample. Yamaha Concert Pianos have their characteristic bright and vibrant tones that cut through a mix and sound brilliant in a concert hall setting.
The Steinway Model D sounds a shade darker and polite with a silky high end. It has a more smoother character.
Both the Yamaha and Steinway carry their distinct trademark voices. You will never mix up the two.
Check out some MP3 demos of third party samples that are readily available for the Yamaha Motif series.
http://www.motifator.com/mart/mainframeVoice.htm You can readily hear the difference between the Yamaha C7 and the Steinway Model D.
Check out some of the custom Organ, Bagpipe, Guitar, Synth and Orchestral voices.
We need something similar for the Tyros2.
Tapas