Who doesn’t like a good bar chord? Nothing against all the supporters of sevenths out there or against anyone who is partial to minors or sixths or diminished, but a solid downstroke on a major bar chord pumps the fist like none other. A sweet windmill-style strike at an axe is a simple surrender to rock. Few bands have ever embraced this power as thoroughly as the self-titled “Loudest Band on Earth.”

One of the most venerated bands of the British Invasion, The Who not only embraced the arena-rock live show, but also broke new ground in rock and pop music. Through his famous operas and other longer, conceptual pieces, guitarist Pete Townshend continuously pushed the band in new directions. But bassist John Enstwile and singer Roger Daltrey didn’t always appreciate the helpful little nudge. After considerable friction, problems with drug abuse, the death of drummer Keith Moon and the trampling of 11 fans at a concert, The Who gradually fell apart, only occasionally launching reunion tours — until now.

After almost a quarter century, The Who have reconvened and released another studio album. Only two original members survive after Enstwile died of a heart attack before a summer tour in 2002. Unlike the Rolling Stones on their recent release, The Who is making no effort to rock like they did back in the day. For the most part, vitality has been replaced with age and wisdom, and while this is probably a good thing for Townshend and Daltrey, it creates a very different effect for their listeners. The accumulation of emotion from The Who’s past and present is evident in the tone and the lyrics of the album, both in the nine initial tracks and in the 10-track long “Wire and Glass, a mini opera.”

The compilation retains a dichotomy between the bar chords and the more subtle elements — apparently born not of inter-band tensions, but rather from a conscious acknowledgement of their own history. Louder, angrier songs that sound like they might come from the ’70s are arranged a little differently, and carry a more nuanced message. While the chorus of “Mike Post Theme” is built around a defiant shout and a windmill guitar stroke, the lyrics play differently: “We’re not strong enough/ We’re not young enough/ We’re not alone enough or cold enough/ Emotionally, we’re not even old enough.” The same feelings of rage and inadequacy are expressed on “It’s Not Enough,” a bluesy growl with a “Teenage Wasteland”-style synthesized arpeggio in the background.

The arrangements of “Mike Post Theme” and “It’s Not Enough” convey this more reflective tone at times as well, when the drums calm down and the guitar becomes a little gentler. There are a few songs that operate only on this level, such as “In the Ether,” a Tom Waitsish love song accompanied only by piano and guitar. “God Speaks of Marty Robbins” and “You Stand by Me” are two notable, beautiful and simple duets between Townshend and Daltrey, and they find a thoughtful place to connect in the chorus of “Robbins”: “Wake and hear the music/ Wake up and hear what the people say.” Both Daltrey’s breathy singing and Townshend’s pointed guitar articulate this simple maxim. When Townshend was accused of possessing child pornography in 2002, he had no more staunch defender than Daltrey, and lines “You stand by me/ You take my side/ Against those who lied” speak to this.

The story of this album is told in “Wire and Glass,” an opera about three kids (unclear why not four) who make a band together, hit it big, run into violence, death and drugs, and then come back together in their old age. “Unholy Trinity,” and “Endless Wire” perfectly capture a sense of hope, promise and breathless excitement for a bright future, culminating in the triumphant “We Got a Hit.” That euphoria breaks sharply and suddenly on “They Made My Dreams Come True,” which seems to be the story of their 1979 Cincinnati concert that killed 11 fans. “Mirror Door” is a live track that celebrates the fabulous power of rock music as well as the inevitable razor edge walked by a rock star. Listing dead musicians, Daltrey wonders “Will there be music, or will there be war?/ Will we be rich, or will we be poor?”

There are songs on this album catchier — or better written and better arranged — than “Tea and Theater,” but the final song of the album is truly touching. It begins with one of the two living band members asking the other “Will you have some tea/ After theater with me?” The song carries self-doubt and self-affirmation; it is a compassionate reflection on a long, wonderful and tumultuous career and friendship. “All of us sad/ All of us free/ Before we walk from the stage/ Two of us/ Will you have some tea?” “Tea and Theater” isn’t a perfect song, and “Endless Wire” isn’t a perfect album, but they are both human, moving and fitting.