If I had never listened to real Duo-Art and Ampico (and Welte)
piano performances, but only to YouTube, I'd never know how good
the performances of such pianos can be!  I agree with Robbie that
YouTube is not a good way for making such comparisons.

There are many alterations of the sound due to the recording
process (dynamic compression by the recording equipment, room
acoustics, quality and placement of microphones, etc.) and also due
to the transmitting process itself (digital processing for video and
audio compression needed for Internet transmission, etc.)  The real
reproducing pianos, when well regulated and with good rolls, have an
astonishing dynamic range that I don't hear from YouTube.

And, lastly, it's hard to compare Ampico to Duo-Art, even playing the
same piece, because of the differences between the rolls themselves.

Leonardo Forti
Italy