i am wondering if anyone knows how to determine if a mic is any good? the only thing i have noticed is that lapel mics seem to have more gain then a headset, but i'm wondering if you were to compare 2 different mics, how would i tell which one is better?
Good manufacturers make good mics.
I have a few cheap no-name-brand electret mics. They sound OK but not excellent and they have a reasonable sensitivity.
I have a very good PRO name-brand electret mic. It sounds excellent and is sensitive but it is expensive.
I have a tiny electret mic from a name-brand cell phone. It also sounds excellent and is sensitive.
The mic in a headset might be designed with a low sensitivity because it is used very close to your mouth where the sounds are loud. You cannot say it is not good because its sensitivity is low.