The default setting Level is – 12 dB, and it works well. Press CTRL + Z to undo if it is necessary to adjust the threshold level. However, you should easily hear if the threshold is set right. The gate is fully closed and produces an absolute silence when closed, and sound may be unnatural.
Choose a part of the audio track that has both sound and silence.Click on Function > Analyze Noise level and take note of the suggested threshold level.Open Noise Gate Effect and select noise only.