Their original version of the song was a major hit in the United States, the UK and elsewhere during 1965. It peaked on the US Billboard Hot 100 chart at number 2, and reached number 1 both on the US Cashbox chart, (Billboard 's main competitor) and in Canada on the RPM national singles chart. It peaked at number 5 in the UK Singles Chart. "A Lover's Concerto" sold more than two million copies and was awarded gold record certification by the R.I.A.A..

The melody of Minuet in G major by Petzold was first popularized by bandleader Freddy Martin in the 1940s; Martin's recording was released under the title "A Lover's Concerto".

Critic Dave Thompson wrote of the Toys' version, "Few records are this perfect. Riding across one of the most deceptively hook-laden melodies ever conceived ... 'A Lover’s Concerto' marks the apogee of the Girl Group sound." The song also had an unusual structure that blurred the differences between its verses and choruses.

The lyrics begin with:

Linzer and Randell based the melody on the familiar "Minuet in G major" (BWV Anh. 114) from J.S. Bach's Notebook for Anna Magdalena Bach. One key difference is that the "Minuet in G major" is written in 3/4 time, whereas "A Lover's Concerto" is arranged in 4/4 time. Although often attributed to Bach himself, the "Minuet in G major" is now believed to have been written by Christian Petzold.

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