It's hard to believe the deflection wasn't artificially enhanced to aid visualization of the waveform.
No kidding! A few years back I attended an audio show in Washington, DC. That evening there was a jazz concert in a room where just 2 hours before I had listened to Hi-Fi. The difference was not subtle. That's when I realized that a ride cymbal is a 19" tweeter.And we expect our speakers to reproduce that wavefront