do we purchase that or as members get it with membership?

There are still some things I'm not grasping from today's FTM seminar (seminar...is that what old people say?). Is there a recommended video that video that can explain this to me like I'm 2? I think one of the most confusing things is calibrating the VU meter to whatever RMS you want (-18, -15, etc). What is the purpose of the meter if it's not measuring something objectively? More questions than that...I checked the classroom not seeing anything corresponding.

Hello! First post here. Title says it all...