to let someone hear (something); to tell or inform someone (by speaking or playing a sound)
子どもたちに昔話を聞かせてあげた。
I told the children a folktale.
先生は授業の最後に重要な注意点を学生たちに聞かせた。
The teacher informed the students of important points at the end of the lesson.
新しい曲を友達に聞かせたい。ぜひ感想を教えてほしい。
I want to play the new song for my friends. I'd love to hear their impressions.
to make someone understand (often by experience); to impress upon someone; to 'teach someone a lesson' (by making them experience something)
上司は部下に、失敗の重大さを身をもって聞かせた。
The boss made the subordinate understand the seriousness of the mistake firsthand.
彼らはチームワークの大切さを試合で思い知らせて聞かせた。
They made the importance of teamwork clear during the match.
失礼な客には礼儀を守らせて聞かせるべきだ、とは言わない方がいい場面もある。
There are situations where it's better not to try to teach rude customers manners by force.
to captivate or grip someone (with singing, storytelling, performance); to enthrall an audience
彼女の朗読は聴衆を聞かせる力がある。
Her reading has the power to captivate the audience.
あの歌手は一曲で観客を聞かせてしまう才能がある。
That singer has the talent to captivate the audience with a single song.