At first, the Koga Melodies became very popular, sung with a technique called crooning based on the strict interpretation of the vocal technique of Ichiro FUJIYAMA (vocalist Takeo MASUNAGA), an orthodox classical singer who graduated from the Tokyo University of the Arts.
古賀メロディーについては、初期、クラシックの正統派・東京芸大出身の藤山一郎（声楽家増永丈夫）の声楽技術を正統に解釈したクルーン唱法で一世を風靡した。