Shield regen sound effect for halo 4 seems wrong

The effect for regenerating your shields sounds physical, like some physical meter being filled up then when full some metal clanks together. I personally think they either over thought this or wanted to unnecessarily change it up. I don’t understand why they would do that though. All the other games seem perfect to me. Energy shields are just that- energy based. Not physical. So what would be at least logical and at most necessary is to make the effect to match. Anyone’s thoughts on this? And please no “oh, you’re way over thinking it” or anything like that. I’m just wandering about something that seems off to me.

I don’t know, maybe when the shields are full the shield generator locks itself via some mechanical components and this is why you hear a metal clank.