降噪Noise Reduction

降噪是去除音频中持续背景噪声（电流声、风扇声、环境底噪）的处理。

• Fairlight 的降噪器通过分析噪声样本，把对应频率成分从录音中减去。
• 先选中一段只有噪声的片段来学习噪声特征，再应用到整段。
• 适度使用，过度降噪会让声音发闷、失真。

Noise reduction removes continuous background noise from audio, such as hum, fan, or room tone.

• Fairlight's denoiser analyzes a noise sample and subtracts that frequency content from the recording.
• Select a section containing only noise to learn the profile, then apply it to the whole clip.
• Use it in moderation; too much makes audio dull and distorted.