No, black holes cannot be directly observed through sound waves. Sound requires a medium, such as air or water, to propagate, and in the vacuum of space where black holes exist, there is no medium to transmit sound waves.
Black holes are incredibly dense objects with an extremely strong gravitational pull. They have such immense gravitational forces that not even light can escape their gravitational grasp once it passes the event horizon, the boundary beyond which nothing can escape.
However, while sound waves cannot travel through the vacuum of space to directly detect black holes, scientists can study black holes indirectly using other means. They use various methods, including observing the effects of a black hole's gravity on nearby matter, detecting X-rays emitted from the heated matter falling into a black hole, or observing the gravitational waves produced by black hole mergers.
These techniques, along with other astronomical observations and theoretical models, have allowed scientists to gather evidence for the existence and properties of black holes, even though they cannot be directly observed through sound waves.