What you'll hear is a combination of a number of tracks - one of the rhythm guitar tracks in the chorus, the lead in the verses and choruses, the slide lead solo at the end of Part 1, one of the slide leads in Part 2, the end acoustic guitar, and the Leslie guitar at the end. Of course, you'll also hear Clapton's lead vocal as well. Here's what to listen for.
1. The high lead guitar in the intro and choruses is doubled, which isn't apparent on the final mix of the record.
2. The high lead guitar leaning to the left plays throughout the verses against Clapton's vocal, which is a violation of basic arrangement rules since it takes attention away from the vocal. Didn't seem to matter in this case though.
3. Clapton's vocal is doubled on the choruses, which again isn't very apparent on the final mix of the record. There's also a lot of reverb on it, and the verb really doesn't sound all that good, which is unusual for the time when everyone was using plates or chambers.
4. Duane Allman's slide solo at the end of Part 1 is truly killer, as he plays up much of it above the fretboard.
5. There are two slide leads on Part 2 (drummer Jim Gordon's piano part of the song). You hear Clapton's part here, which changes to an acoustic guitar during the last verse.
6. Check out the Leslie guitar at the very end at 5:25. Criteria Recording (where the song was cut) had one of the first guitar input devices for the Leslie that could vary the speed with a footswitch and Clapton loved it (and reportedly absconded with it back to England after the session). There's plenty more on Leslie guitar on the final mix, but you only hear that one piece here.
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