Listen to Solfeggio Frequency (174Hz) Courteous Frequencies Serenity online. Solfeggio Frequency (174Hz) Courteous Frequencies Serenity is an Instrumental language song and is sung by Tmang. Solfeggio Frequency (174Hz) Courteous Frequencies Serenity, from the album Solfeggio Frequencies Calmness, was released in the year 2024. The duration of the song is 1:00:00. Download Instrumental songs online from JioSaavn.