I’m not sure if there is much of an answer for my question but nothing ventured, nothing gained as they say.
I’d like to remove as much of the bass guitar as possible from an MP3 audio file so I can record and mix my bass to replace the original bass line.
Thru experimentation I have found that using the High Pass Filter at 300Hz and a roll off of 48dB/octave removes enough of the bass guitar to be acceptable for my needs. The problem is that after doing this filtering the result sort of sounds like what you might hear from a pair of earbuds placed on a table across the room or a 1960s vintage transistor radio. It’s not the lack of volume that’s the problem but a lack of overall fullness. I think what is happening is there is enough frequency content below 300 Hz in acoustic guitar, keyboard and other instruments that contribute to the overall fullness of the song. Even though these frequencies are not coming from the bass guitar they are also removed in the filtering. Even with my bass included into the mix these instruments sound thin and tinny. My bassline is adequately full sounding in the mixed recording.
So is there an effect that I can apply to the audio waveform either after the high-pass filtering or after my bass has been mixed in that would restore some of the overall fullness of the acoustic guitar, keyboard and other instruments to make them sound less thin?
One idea on how to maybe do this would be to identify each instrument in the mix (or even 2 or 3 of them) and add frequency content that is 1 octave below their lowest frequency. This could restore some of the lost fullness without adding back any bassline. If Audacity can’t do this is this a reasonable feature for a future version?
Any thoughts would be appreciated.