Recording BACKGROUND NOISE SUPPRESSION The BACKGROUND NOISE SUPPRESSION effect levy emphasizes the frequency age of the human voe while reducing both the ngh and the low frequencies that usually comprise Norse. «Set the BNS (Background Noise Suppression) switch to ON to achieve a clearer and better defined voice recording in noisy SUTGURMIRGS. ~You can use VOICE ACT with the BNS {Background Noise Suppression} during recording.