Whilst agreeing with the comments about harmonics of 60Hz being present, you may get acceptable results just filtering out the 60Hz with a notch filter or a High Pass Filter. A noise filter is meant for getting rid of hiss etc. not specific frequencies.

Unfortunately the lowest note on a 4-string bass guitar is 41.2 Hz (not 80 as suggested above) so you may lose notes around B(61.74Hz).

Audacity has an FFT filter and a High Pass Filter which may be sufficient but it also has a "Nyquist Prompt" which you can program to remove specific frequencies or you can download a notch filter plugin at http://audacity.sourceforge.net/nyquist/notch.zip.

Mitch