Vocaloid Technology

The Vocaloid singing synthesizer technology is categorized as concatenative synthesis, which splices and processes vocal fragments extracted from human singing voices in the frequency domain. In singing synthesis, the system produces realistic voices by adding information of vocal expressions like vibrato to score information. The Vocaloid synthesis technology was initially called "Frequency-domain Singing Articulation Splicing and Shaping" (周波数ドメイン歌唱アーティキュレーション接続法 Shūhasū-domain Kashō Articulation Setsuzoku-hō), although Yamaha no longer uses this name on its websites. "Singing Articulation" is explained as "vocal expressions" such as vibrato and vocal fragments necessary for singing. The Vocaloid and Vocaloid 2 synthesis engines are designed for singing, not reading text aloud. They cannot naturally replicate singing expressions like hoarse voices or shouts, either.