It's so hot these days, isn't it? How are you doing everyone? It is in Japanese culture to listen to cool sounds. Have you heard the sound of a wind chime? They are made of different material such as glass or iron etc... The sound feels cool and comfortable / The sound is pleasing to the ear. If you would like to rest, I recommend you listen to the sound of chimes. https://youtu.be/RaPOxXl5Mfw