It's one of the few songs by the band that's actually credited to all three band members as authors, which in this case came about after a number of arrangement changes by bassist Krist Novoselic and drummer Dave Grohl to the song that guitarist Curt Cobain brought into rehearsal.
Here are the isolated vocals from that song (which begins at 0:33) as well as what to listen for:
1. The lead vocal has an interesting reverb that sounds more like a long delayed ambience than a typical plate or hall effect. It's delayed and fairly short and dark so it blends into the track well.
2. Take notice that the B-section vocal is doubled and spread out in stereo a little to the left and right. The left vocal is a little drier than the right side, which is pushed back in the mix a very short amount.
3. The last lines of the verses and chorus again feature a doubled lead vocal that's back in the center of the mix.
4. Listen to the sounds of the open mic before the second verse at 1:40.
5. Listen all the way through to the end to hear the ending that didn't make the record.
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