if i get all my tracks to a volume im satisfied with (i.e the parts i want to be loud are loud, the parts i want to be subtle are quiet, etc), but the track is peaking say 3db, what would be the difference of just turning the master track volume down to create headroom, as opposed to leaving the master track at 0db and altering individual tracks until i create enough headroom? I've read numerous times not to touch the master track db and to keep it at 0, but what is the difference if I just pull the master track db down instead of pulling down the db of other tracks such as the snare, or synth lead? In the end, there will be the same amount of headroom, but there's these two ways of going about it. Will dynamics be affected if I pull down the db of the master track instead of several individual tracks? thanks

hey can anyone help me make this pluck sound that comes in at around the 00:32 mark in the background? is it a sine wave? thanks!

https://www.youtube.com/watch?v=uCmJmOineVg