Of course, even if you call it sound, it's too low for anyone to hear.

当然，即使你称之为声音，但它也太低了以致没有人能听得到。

youdao

Sound, light, smell, the beds too soft or too hard, too high or too low indoor temperature, mosquitoes, flies or tick bites, etc., will interfere with sleep.

声音、光线、气味，床铺太软或太硬，室内温度太高或太低，蚊、蝇或虱的叮咬等，都会干扰睡眠。

youdao

The object was not a helicopter because it made no sound, and not a plane because it was too low and did not move.

对象不是因为它没有直升机的声音，而不是飞机，因为它太低，没有动。

youdao