10. All My Love
Quickly expanding beyond their bluesy roots, Zeppelin spent much of the back half their career stretching the boundaries of where the rock song could go. Rather than just plod away on a Jimmy Page riff, this delicate song from In Through The Out Door has its roots with John Paul Jones.
The entire track is centered around Jones's keyboard work, which was created using the Yamaha GX-1. The otherworldly sound of this synthesizer ended up kickstarting a whole generation of musicians aching to get that ethereal sound in their own tunes. "All My Love" is much more than just its instrumentation though.
The lyrics are some of the most heartfelt that Robert Plant had ever written up to that point. Rather than writing generic love lyrics, this track is written in tribute to Plant's young son who had passed away while he was on tour. Though Jimmy Page may not have had a hand in writing the track, the subtle bends that he does throughout the song's breakdown give an extra layer of dramatic weight to this already emotional piece.
Zeppelin is known for songs that can tear your head off, but they were certainly able to write slowjams that could tug at your heartstrings as well.