youdao

His voice dropped to a lower pitch.

他的声音降到较低的音调。

youdao

The note of the whistle is heard to change to a lower pitch.

汽笛的音调听起来就越变越低了。

youdao

Scientists also recorded countryside great tits and found they sang at a lower pitch and, in turn, city birds found the rural droll difficult to understand, the study found.

BBC: Birds in cities 'singing louder'

Rural birds were confused by urban bird song while city birds "didn't understand the lower rural pitch".

BBC: Birds in cities 'singing louder'

He can then slowly lower his usual speaking pitch to that note.

FORBES: How You Can Profit From The Massachusetts Gubernatorial Race