

If it is a studio recording of music with vocals since 1980-90, I would put money on there being some correction on the vocals. If it is a studio recording of music with vocals since 2000, i would put money on there being some use of autotune or melodyne or a similar pitch correction software/hardware.

But autotune and melodyne can be… Tuned :) much like vfx in movies, it is at its best when you can’t tell it’s there