I'll add - the turn on / off sequence applies to all audio gear.
It is very important with pro-audio equipment. For example, a 2KW power amp has a very big thump due to being turned on first, and then the pre-amp / mixer is turned on second. Besides, scaring the crap out of you, it can put a big dent in the pocket book.
A good reason to have a power sequencer for some installations.
Just get an idea of how long your equipment pieces take to turn on. For me, I had to learn to wait a little longer after upgrading a Foreplay III to ext Foreplay III; need to wait a little longer for the current sources to light up.