Noise reduction plugin problems...

[jnorman]

i just started experimenting with a noise reduction plugin (ReaFir in Reaper). as normal, you let it sample a short passage of background noise, and let it build a noise profile. then the plugin subtracts that from the track.

well, it really does greatly reduce background noise, but it is also resulting in a large reduction in the high frequency content of the track(s). i am not sure why...

should i continue to use the plug, and then compensate by additive EQ in the upper freqs? or should i not use the plug at all? or am i using it incorrectly somehow? or is ReaFir just junk and i need a better version of NR software? thanks.

[BrianHanke]

Strange... I use it all the time with no high-frequency loss. I have Reaper version 2.55. ReaFir can be a bit finicky sometimes: it only seems to work properly when you follow the exact right series of steps.

[rumleymusic]

Not all NR plugins are created equal. Some are just glorified EQ's that affect everything and for the most part are useless. (sound soap). Some, actually the majority, add some controls to avoid attenuating certain frequencies and allow you to adjust the threshold of the noise reduction (Audition, Sony). In this case the are more noise gates than true NR algorithms. The most advanced use special processes to determine what is music, what is noise, and allow adjustments for the user to fine tune the type and level of noise reduction. These cut around the sound that you do not want affected. (RX, Algorithmix, Cedar).

Most integrated plugins are either the first or second category. If you want really good results, you need the third category.

[imgoinmad]

Are you removing too much at once? I don't use that plugin but have used similar. I generally sample the sound i want to remove and then rather than removing completely in one pass, I remove less of that sound in 2 or 3 passes. Seems to give better results than trying to get it all in a single pass.