User:PeterSampson/Sand-Box

Gale 22Oct13: Personals like "I" and "my" are inappropriate in the Manual especially if they appear to be criticising Audacity as this comment is. See also the settings advice on the Wiki ( http://wiki.audacityteam.org/wiki/Noise_Removal#Improved_Noise_Removal_in_current_Audacity ). If you want this in then you need to rewrite it impartially (an "example" is appropriate for this IMO, but it does not seem much of an "example" with only two settings changed. Why not make an example (using the agreed example div) of a lot of noise within the music, where pushing the sensitivity slider up is the key? This seems to be the more common complaint about current noise removal - or isn't it? Steve 22Ict13: Fwiw, I agree that personals like "I" and "my" are inappropriate for the manual, but I don't agree that the comment is being (negatively) critical of Audacity.

A skilled user of Audacity offers this advice on the use of Noise Removal:

The default settings in Noise Removal are a bit too aggressive for my liking, but many users require the settings to be quite aggressive so as to have some impact on bad recordings. Setting the "Noise Reduction (dB)" to about -12 will still have an appreciable effect on low level noise, but will produce much lower tinkly artefacts than the default settings. I generally like to increase the "Frequency Smoothing" a bit too - typically around 500 Hz, but for critical work it's best to experiment for optimum settings.

The "Sensitivity" control is interesting, but a bit tricky to use effectively. Usually I leave this at the default 0.0 dB. Some sounds "mask" noise better than others. Sounds that have a significant amount of "breathyness" will cover up (mask) low level hiss much better than say low piano notes.

When the noise is not masked, it will be audible "through" the retained sound. This can be countered by increasing the Sensitivity (dB) control, but note that increasing the sensitivity makes the effect more aggressive so it is also necessary to reduce the "Noise reduction (dB)" setting and possibly also increase the "Frequency Smoothing" and reduce the Attack/decay to zero. For this type of situation I may increase the sensitivity up to about +8 dB and reduce the reduction to around 8 dB.

Reducing the sensitivity control can help to make the effect less aggressive, though personally I find that reducing the "Noise reduction (dB)" control does this better.