You can have a vocal fairly prominent in the in-ear mix without as much of the harsh sibilance from the voice, or from cymbal bleed.

你能够听到十分突出的人声效果，而没有那么多人声中的尖锐的嘶嘶声(齿音？)或者铜钹发出的带刺儿的声音。

youdao

But in the darkened chapel it was so silent he could hear the faint sweet sibilance as knuckling flames consumed the wicks of the votive candles.

NPR: Excerpt: 'Exiles'

This is also when his annoying sibilance kicks in.

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