I used sony hc40 recorded a presentation in classroom. The sound quality was not very good lot of noise. I used Audition's noise reduction filter, it can remove the noise, but speaker's voice becomes funny. I appreciate if some one can tell how to fix this problem.

Not always an easy job doing this. Much easier if you have a section of audio that contains just the noise you want to remove.

What you need to do is highlight a section of your recording that only contains noise. Capture that as a 'noise profile'. Then use the noise filter with that profile across the entire recording. Lots of parameters to play with.

The principals are exactly the same as a version or two ago so the tutorial at Wrigleyvideo should still apply.

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