Disklavier

How embarrassing. Sorry for my dyslexia. I meant a U1SG.

http://usa.yamaha.com/products/musical-instruments/keyboards/silentpianos/upright_pianos/u1sg/?mode=model

I have had my piano technician fully tune the piano, and it sounds fine (very nice!) acoustically. He agreed with me that the digital samples demonstrated the qualities that I described, but again, he thought that this just might be the way the samples were created  (i.e., there is no dysfunction, but the samples could have been done better in the first place). 

I felt that it would be odd for Yamaha to have done a better job (regarding the sustain sounds) on the samples for strings, vibraphone, etc., than the acoustic piano (i.e., the former fade more realistically with the sustain pedal engaged). This is why I was wondering.

Given your extensive experience, and your helpful answer, I will just do my best to see if I can find another U1SG to play to see if this model always sounds this way. I will also ask if they might send a Yamaha technician out to inspect the sensor placements.

Thank you.