OK
So let's try to take the jewish way of trying to explain things..
Take some lipstick from you wife and use it.
Now ,you changed your look. But wippe the lipstick and you look the same than before, put it again and you change you look.
This is Replay gain: you play a playlist? Put some lipstick and you get all the tracks at the same level.
You want to play a full album? Remove or do not put lipsky.
You will get the natural look== all the songs playing as on the original cd.
Now ,you do not take lipstick from your wife , but you have a M Jackson trip : you make a tatoo who looks as you had put lipstick. This is for ever ,you have it and you keep it
Well we know that M Jackson with the skins of 3 virgins ,200 ckickens and 500 turkeys can still change it .
But you , you cannot afford 500 turkeys , so you stay with your 'look like i put some lipstick' tatoo.
This is MP3Gain.
So if you play often the same songs than on the cds from MC ,yes ,the best thing to do it to make a playlist " to be Mp3Gain and burn"
My problem concerning metal was to find the right settings , who are NOt the same than other kinds of music.
Still listening to Alpha Blondie -15 albums in a row-