Some mastering engineers are still trying to make a track sound as loud as possible. They still believe we’re in a war, the loudness war. Well, guess what?
War is over! Give peace a chance!
A streaming service like Spotify has Volume Normalization activated by default. YouTube? Same thing. iTunes Radio/Music? Also, yes. And it is bloody fantastic. I have ALWAYS been a huge fan of Replay Gain / Volume Normalization because it evens volume levels in such a nice way. You can disable it which might be useful for some classical music, but in general the even balance between tracks is just super convenient. So I would advice anyone to leave it on all the time!
Most loudly mastered songs will sound like shit when you compensate their levels. A lot of music is mastered badly (read: the mastering idiot killed all the dynamics) and there’s nothing you can do about it. When dynamics are gone, nothing will help to bring them back to life. Gone forevah! Remastering…
Now what? Well, mix as dynamic as you can and as you would like. Loudness is no longer something you should worry about AT ALL.
P.S. for your information: Spotify uses Ogg Vorbis on 320 kbps for Premium users. It sounds just fantastic!