Los Tremendos Gavilanes is a norteño group formed in 1957 by Juan Torres (Accordianst & Backing Vocals), Salomon Prado (Bajo Sexto & Lead Vocals), and Isidro Chavez (Tololoche/Double Bass). They hail from the famous region of Monterrey, Nuevo Leon, Mexico, where many norteño artists got their start in the music business.