Here are a couple of things to listen for during Ringo's isolated vocal:
1) Ringo's vocal track is generally pretty good for someone that's not a great singer, but it's ironic that the one place he's out of key is at the end of the first verse when he sings, "I will try not to sing out of key." He's a little flat on "key."
2) There's a significant amount of leakage in the track. I believe this was before the time they wore headphones for vocal overdubs so you're hearing the playback from the Lockwood speakers. I'll check with Ken Scott about this.
3) The Abbey Road reverb sounds great on both the lead and background vocals. I suspect that there's a separate chamber on each since the verb sounds different.
4) Great background vocals, as usually. Very tight during the song, although not so on the outro/lead-in to the song.
5) There's an interesting accidental word at 1:51 that appears to be on the background track that was left in.
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