Insert a period (.) followed by a soft pause. Yumi’s voice model includes natural inhalation phonemes if you write: 안녕하세요. . . 저는 유미입니다.

Ensure your input text is Unicode (UTF-8) . Yumi VW37 fails with ANSI Korean. Use a text editor like Notepad++ to convert.

Even with VW37, default output can be flat. To get studio-quality Korean narration:

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