I did say I would include only one U2 album. Like I said, I could easily have included all of them in this list, but this is the one that stands out for me. Yes, more so than the Joshua Tree. You see, most U2 fans became U2 fans with the Joshua Tree. Those of us who were fans before, can really appreciate the impact this album had on us! This album set the tone for the Joshua Tree.
With this album U2 made a very risky decision in changing producers, leaving a very capable one in Steve Lillywhite, who produced their first three albums, the last one "War" is the one that hooked me to U2. Just so know how good Steve is, he's been credited on over 500 albums, from Rolling Stones to Peter Gabriel, from Talking Heads to The Counting Crows.
Why the change? U2 were looking to move in a different direction from their initial three albums. Experementation was the key word. So, they chose a castle to record their sound in, and chased down Brian Eno to produce it. Island Records were so freaked out by the choice of Brian Eno, that they did all they could to convince U2 not to use him. Eno himself was not too keen to produce it. In fact he brought along his sound engineer, Daniel Lanois, with the hope of convincing the band to use him instead. In the end, both Eno and Lanois produced the album. The two of them became the foundation of the new U2 sound which matured in The Joshua Tree.
Every song is brilliant, intensely deep and rich in sound. The raw energy of "War" was all but gone on this album, replaced by a more cohesive, flowing sound. Bought this in 1985 (along with "The Unforgettable Fire" Mini Album that included 4 bonus songs). Played this to death.