I once had a teacher who said that if you understand classical music, you wouldn't listen to anything else. That's obviously a wild exaggeration and completely pompous, and as these seven musicians proved, it is completely possible to love both classical and rock music. Here are seven rock stars that also write classical music.

1. Paul McCartney

Paul McCartney may be known for his intricate and harmonically rich songwriting, but he's actually a completely untrained musician, with no knowledge of how to read music whatsoever. Though reading music might seem like a prerequisite for pursuing classical music, McCartney has ventured into the genre many times, starting as early as 1966 with the score to the film The Family Way, which some consider to be the very first Beatles solo album.

2. Roger Waters

Though Roger Waters may have been the least technically talented member of Pink Floyd, he's the only member to have worked in classical music. In 1988, Waters wrote a three-act opera about the French Revolution titled Ça Ira, which was eventually released in 2005, and though it technically wasn't the first opera he wrote (that would be Pink Floyd's rock opera The Wall) it was his first foray into traditional, classical opera.

3. Frank Zappa

Absurd humor and mind-bending eccentricity might be the most visible traits of Frank Zappa's music, but beneath all of the silliness lies some of the most complex and unpredictable rock music ever written. All of this complexity can be traced back to Zappa's love of classical composers such as Stravinsky and Varèse, and this classical influence occasionally found its way into his work, such as his debut solo album Lumpy Gravy, or the last album he released during his lifetime, The Yellow Shark.

4. Jonny Greenwood

Not only is Jonny Greenwood the youngest member of Radiohead, he's also the only member without a college degree, and the only member with classical training. Greenwood's love of classical music is well known, as he wrote about recently for the Guardian, and though he's yet to release an official solo album of classical work, Greenwood is the composer-in-residence for the BBC Concert Orchestra, and has composed scores for such films as There Will Be Blood and The Master.

5. Bryce Dessner

Though his twin brother Aaron Dessner is the primary composer for the National, Bryce Dessner is an acclaimed composer in his own right, collaborating with artists such as the Kronos Quartet and Radiohead's Jonny Greenwood on classical and chamber music pieces.

6. Glenn Danzig

Glenn Danzig's work with the Misfits and Danzig was always more melodic than his thrashy contemporaries, but classical music is not something I would have expected from someone so deeply involved with punk, blues, and metal. He's released two albums of dark neoclassical music, Black Aria and Black Aria II, which are technically the only solo albums he's ever released.

7. John Paul Jones

Robert Plant and Jimmy Page may be the faces of Led Zeppelin, but bassist John Paul Jones was the band's secret weapon, co-writing many of the band's greatest songs such as "Black Dog" and "Communication Breakdown." Since the breakup of Led Zeppelin, Jones has occasionally worked in classical composition, including film scores and even providing the orchestration for R.E.M.'s Automatic for the People in 1992.