background sound

基本解释

During a shoot, mic placement is optimized for dialog, and the quality of background sounds can suffer.
射击时，麦克风的摆位要照顾对白，就可能导致背景声音的音质大打折扣。
When natural background sounds, like the engine tickover of a parked car, were added, the hybrids’ direction sometimes could not be detected until they were perilously close.
如果添加诸如停车时发动机的空转此类自然背景音，有时混合型汽车的方向在危险距离之前根本无从判断。
Now listen to the background sounds, feel the fabric of your clothes, feel the weight of your seat on the chair, your feet on the floor; use your senses.
现在运用你的感官：听听周围的声音，感觉你衣服的纹理，感受你对椅子施加的压力，还有你放在地板上的双脚。

The sounds would need to be detectable under a wide range of street noises and other ambient background sounds when the vehicle is traveling under 18 miles per hour.
ENGADGET: NHTSA details new sound requirements for hybrids and EVs travelling under 18 mph
When I travel I have Classic FM streaming in the background and it sounds fine.
FORBES: In Praise Of...The Netbook?
During signed dialogue we hear nothing but a trickling fountain in the background, or the sounds of distant crowds.
NEWYORKER: Seen but Not Heard