“高声发出”可以翻译为“emit loudly” 或者 “utter loudly” ，也可根据具体语境用“raise one's voice to say/emit” 等表达。以下为不同例句：
The alarm emitted loudly, alerting everyone in the building. 警报高声发出，提醒了楼里的所有人。
She uttered loudly a cry of pain. 她高声发出痛苦的叫声。
He raised his voice to say something important. 他提高声音说了一件重要的事 。