On the 2015 "remastered" version of Warner Bros. Records, it is clear from listening (and analysis) that the average level has been raised by +7 dB, achieving a "peaks" limitation. So there is less need to increase the volume, but since we adjust the listening volume compared to an "average" level, the very slight difference that we perceive when listening is the addition of the Odd and Even Harmonic generated by the important limitation of the Peaks.