An Audience was dumfounded:

On a very snowy evening in the late '60s, two musicians somehow managed to get to Trenton to play a concert. They were: Paula Robison, well-known flutist, and a fine young harpsichordist named Frances Cole. Ms. Cole had recently switched from viola to harpsichord. She would have become famous had she not soon after succumbed to a fatal disease.
The concert took place in a small room that could easily hold 150 people, but due to the snow there were perhaps 30 listeners. The concert began with a short unaccompanied flute piece, Debussy's Syrinx. Then the two played a gentle baroque flute sonata. Frances Cole closed out the first half with a set of Couperin pieces.
Now the harpsichord is a quiet instrument, especially in comparison to the piano. The audience had adjusted - more than they knew - to the tinkling of the harpsichord before the Couperin began. This was music that built up to quite a climax, and Cole's specially built harpsichord was capable of more power than most. Near the end she switched to quadruple and quintuple octave coupling and brought the piece to a thrilling conclusion. The audience, used to thinking of this instrument as a rather puny thing, were bathed in a torrent of sound. They applauded enthusiastically. Frances Cole took her bow and walked offstage.
But what was interesting was what happened the moment the performer was out of sight. The entire audience swarmed up onto the stage, surrounding the harpsichord, and examined it in amazement.