brief LIVE demo on 40 meters RX - of using the Noise-repellent LV2 PLUGIN to lower(or even virtually eliminate) the HF Background audio static while listening to a CW SIGNAL
(this plugin works well on VOICE too)
FROM THE DOCS on this plugin:
find a clear spot on the HF BAND of interest then: - Turn on "learn noise profile" for a bit...once that's done turn it off and tweak (the other) parameters (on the plugin) as you like.
Advice for better reduction
General noise reduction advice
* Try to reduce and not remove entirely the noise. It will sound better.
* Gentler settings with multiple instance of the plug-in will probably sound better than too much reduction with one instance. Of course for every instance the noise should be re-learned again.
* If the noise varies to much from one section to other apply different reduction for each part.
* Always remember to listen to the residual signal to make sure that you are not distorting the signal too much.
* Start with the reduction at 0 dB and then decrease it until you hear artifacts then tune the parameters to get rid of them without distorting the signal.
* It might help using an spectrogram analysis to help you notice what you are doing. This can be easily done by using a-Inline Spectrogram in Ardour or the spectrogram view in audacity or sonic visualizer