As we spend this weekend celebrating the 50th anniversary of the Summer of Love on KDFC, one of the most important albums of that era was released by The Beatles in the first week of June, 1967: Sgt. Pepper’s Lonely Hearts Club Band. With its songwriting and performance, studio techniques, and unusual instruments added to the equation, it changed the way the public thought about popular music.

The name of Sheila Bromberg probably isn’t familiar to those who aren’t avid Beatles fans, but her contribution to the Sgt. Pepper album is instantly recognizable. Bromberg was hired for nine pounds to play harp on a nighttime recording session, not knowing who she’d be playing for until she got there, when she learned it was for the song She’s Leaving Home. Producer George Martin got to play harpsichord (Fixing a Hole) and harmonium (A Day in the Life) and led the 40 piece orchestra through the dream sequence of that song. Each musician was given a starting and ending note, running from the low to the high end of their instrument’s extremes, and over the course of 24 bars, they were told to continually crescendo. Two other ’67 Beatles songs feature an instrument you wouldn’t expect to find on a rock-and-roll record. Paul McCartney had heard David Mason play the piccolo trumpet in a performance of Bach’s Brandenburg Concerto No. 2, and wrote a Bach-inspired solo for him to play on Penny Lane. That song was recorded for Sgt. Pepper, but instead released with Strawberry Fields Forever as a double A-side single earlier in the Spring. He also makes an appearance on the song All You Need is Love, quoting Bach in its closing moments.