Sound therapy, also known as sound meditation.
It is an alternative and complementary therapy that uses sound to promote relaxation, reduce stress, and support overall well-being. 
It's based on the idea that sound vibrations can have a positive impact on the body, mind, and emotions. 
There are various ways in which sound can be used as therapy, some of them I have encountered personally, they are as follows:

Singing Bowls: Singing bowls are traditional instruments made of metal that are struck or played with a mallet. When the bowl is played, it produces a soothing and resonant sound. The vibrations from the bowl are thought to create a sense of calm and balance in the body and mind.

Gongs: The Tibetan gongs are very famous for meditation. Gong therapy involves playing large gongs to produce deep and complex tones. The vibrations from gongs are believed to create a sense of deep relaxation and help release tension and emotional blockages.

Music Therapy: We all love music. Listening to soothing and calming music can also be a form of sound therapy. Music has the ability to evoke emotions, influence mood, and reduce stress. Music therapy is often used in clinical settings to support mental and emotional well-being.

Guided Sound Meditations: Practitioners guide participants through meditation sessions accompanied by sounds such as nature sounds, Tibetan bowls, or other calming sounds. These sessions are designed to induce relaxation and mindfulness.

Sound therapy is often used as a complementary approach alongside other therapies and practices. 
The sound therapy may not be suitable to everyone, but many individuals report positive experiences in terms of relaxation, stress reduction, and improved mood.