I have version 2.0.5. The Quick Help topic on Effects lists the Notch filter under “Nyquist plug-ins included in Audacity,” but it does not appear in my Effects menu. I need an Effect to remove background hum, and this seems to be the effect I need.
Does anyone know why this might be missing, and what to do about it?
My notch filter is near the bottom of the listing. The list is in two segments.
2.0.5 is now obsolete. If you go to http://audacityteam.org/download/windows you can get the current 2.0.6. Download the installer, and half way through the installation process, enable the box to “Reset Preferences”. This should fix all possible causes of the problem.