This is a very difficult question to answer because there are many factors that are involved when playing quietly.The first and most important quality is the choice of instrument. Obviously a 9 foot concert grand is capable of producing huge sounds. Where as a smaller grand could produce softer tones due to the shorter length of strings.The next factor would be where one would be seated in a concert hall. Are you close to the piano, behind the piano (facing the opposite side to the lid)?