In the beginning of all things, I wasn't there. Now I'm seemingly everywhere.
With or without an orchestra, you can't listen to me unless I'm conducting.
I know not of my birth, since my parents sacrificed themselves so that I could be.
I only know that things were hot and there was a lot of pressure to make me.
What am I?
Hint:
The riddle does contain some misdirection and some double meanings.
Here are some helpful wikipedia articles related to the clues for those who have solved the riddle and want to know more:
In the beginning of all things, I wasn't there. Now I'm seemingly everywhere.
With or without an orchestra, you can't listen to me
unless I'm conducting.
I know not of my birth, since my parents sacrificed themselves so that I could be.
I only know that things were hot and there was a lot of pressure to make me.