Freemium

where you invert the phase of one track and mix it with the other to cancel out the common elements. This works well for removing vocals from a song, but it can also be used to isolate individual instruments. Another approach is using spectral editing, where you can visually identify and remove specific frequencies from a track. This technique is more time-consuming but can yield better results for complex recordings. There are several free audio editing software options available, such as Audacity and Ocenaudio, that offer these features and more. With a little practice and experimentation, you can achieve near-perfect isolation for your recordings without breaking the bank.