| 84 / | HD | MUSIC |
| 1 | DF | INSTRUMENTS {9} |
| 600 | DF | .~ Electrical musical tone generation {5} |
| 723 | DF | .~.~ Transducers {9} |
| 725 | DF | .~.~.~ Electromagnetic {2} |
| 726 | ![]() | .~.~.~.~ String {2} |
| 727 | DF | .~.~.~.~.~> With adjustable means |
| 728 | DF | .~.~.~.~.~> Noise reduction (e.g., error prevention) |