1) Listen to the majesty of Ann Wilson's voice. One of the best voices in rock.
2) As with most songs done in the analog age, there are a lot of lip smacks and breaths (thanks to the hard compression) that couldn't easily be cleaned up in those days.
3) It sounds like there's an 8th note delay with a fair amount of regeneration on the vocal that's timed to the track and printed. The reason why I think it's printed is that you can hear a punch at about 12 seconds where the delay cuts off and then back in again.
4) The production on this song is state-of-the-art not only for those days, but now as well. Listen to electric rhythm guitar and acoustic guitar during the guitar solo at around 2:00. They're really tightly played with each other where it almost sounds like they were fixed by moving sliding them in a DAW, which of course wasn't available for about another 20 years. Also, the layering of the outro is great.
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