All commercial recordings unfortunately are not in tune with concert pitch A440 tuning. I need to correct this on a few specific MP3 recordings so that I can play an instrument along with them without having to retune from song to song. How to do this. Thank you.
Put a small weight on your turntable to adjust the spin speed.
But in all seriousness. Audacity includes a pitch shift, and it's free.
Yes, many songs are sped up or slowed down post recording which also changed the pitch. Annoying for playing along or learning. I use "The Amazing Slowdowner" program to learn solos and tricky parts but you can also saved processed songs. You can adjust the speed down or up by hundreds of a second and the pitch by cents. You can keep the speed and just adjust the pitch or vice versa. I know there are many recording software that will do this too just as well (about any of them) but this is just an easy small pop up window program that only does these things. You can also crop and re-eq it.