[1] Born in Bath, Somerset, England, of Italian ancestry, Semprini showed early talent for both the piano and cello.

The second of three sons, his parents were Arturo Riccardo Fernando Semprini, a musician from Rimini, Italy, and his wife, Elizabeth Tilley, an opera singer from Dudley, Worcestershire.

Alberto graduated from the Verdi Conservatory in Milan in 1929, having studied composition and conducting, as well as honing his skills at the piano.

[1] In Italy, he performed a broad range of music, from pop to jazz and classical, and in 1938 led his first radio orchestra there.

While working with ENSA, he met the actor Michael Brennan, who helped Semprini get his passport back.

[2] Back in the UK, he hosted a light music programme, Semprini Serenade, which he introduced with the words: "Old ones, new ones, loved ones, neglected ones".

His work was first released on the Italian label Fonit Cetra, then EMI Records, where he remained for the rest of his professional career.