For silencing High Voltage in Turn 1 and Turn 2 you'll need two classes with silence to cover them all. Just coordinate with your other silence class which of you will take the first silence, then just alternate back and forth.

There aren't a lot of other times you'll have to worry about silence, so in most cases you'll just want to use Blunt Arrow as extra DPS filler in between your global cooldowns every time it's up.