See anytune.app/reframe for some details on ReFrame . You can try it for free on iOS with Anytune Free and on Mac with the Mac 30 Day Trial. If the instrument or vocals are contained in a unique position on stage and frequency range they can be soloed or muted. This will work better for some songs than others.
Anytune also has an Export Feature that will create a modified audio file. When you export a song you can export the Original Song (unaltered) OR a Tuned Song which includes all the current settings including ReFrame, Tempo, Pitch, Gain, Pan, EQ, Retune, and even the current loop.
This is included with Anytune Mac but is included with the Export Pack Add-On available as an In-App-Purchase. The export option is a one time purchase. You do not need to purchase it per song. Once the functionality is unlocked, it is yours to use as you like. It is also transferable to any of your iOS devices (or a new device if you get one) by using the “Restore Purchases” option in the in-app Anytune store.