Heart of Glass
by Blondie
- 117
- BPM
- E major
- Key
- 12B
- Camelot
- 70
- Danceability
- 2
- Acousticness
Blondie recorded "Heart of Glass" at the Record Plant in New York in June 1978. Producer Mike Chapman had asked them to play every song they had, and at the end he asked if they had anything else. They sheepishly offered an old one. Debbie Harry and Chris Stein had written an early version, "Once I Had a Love", in 1974 or 1975, and the band called it "The Disco Song". They had tried it as a ballad and as reggae without success.
The production was built around a Roland CR-78 drum machine, new in 1978. It was among the earliest uses of the machine in popular music. The machine was blended with real drums, and the bass drum was recorded on its own track. The CR-78 also sent a trigger pulse to early polyphonic synthesizers. That became a distinctive element of the track. A Roland SH-5 and a Minimoog were also used, and with no sequencers they recorded three separate synthesizer parts. Harry's voice was double-tracked.
Chris Stein said they were into Kraftwerk and wanted a more electronic sound, closer to Euro disco. The title came from Werner Herzog's 1976 film, though none of the group had seen it. Chrysalis released the song as a single in January 1979, and it reached number one in the US and the UK.
Heart of Glass runs at 117 BPM, the tempo of pop, funk and disco-leaning dance. In classical terms it sits in moderato territory. A bar of 4/4 lasts 2.05 seconds, and a quarter-note delay is 513 ms. It is in E major, Camelot 12B, which shares its notes with C# minor and mixes cleanly with A major and B major.
We use multiple sources as part of our online research for the song story including Wikipedia.