One of many things I did not expect to learn in this book is that the BBC benefited from Nazi technology. Its standard tape recorder, in use till the 1970s, was called the BTR-2: EMI’s original model, the BTR-1, had been copied from a captured example of the German “magnetophon”, as used by Hitler to record a radio broadcast.
Musicians who liked fiddling with machines, too, benefited from this legacy. Delia Derbyshire, the BBC Radiophonic Workshop pioneer who produced the original Doctor Who theme tune and otherwise particularly enjoyed playing an enamel green lampshade, influenced Paul McCartney’s experiments with tape loops, while Steve Reich hit upon his compositional technique of “phasing” phrases in and out of sync with one another on tape recorders, before training live musicians to do the same.
Many other revolutions occurred in sheds and back rooms. Bob Moog, a musically trained engineer, invented his electronic synthesiser in his garage. Along with other synths such as the Buchla, it was initially used by avant garde classical composers such as the great Karlheinz Stockhausen, then deployed by psychedelic rockers in the 1960s, before eventually Giorgio Moroder used a Moog for the bass part on Donna Summer’s futurist-disco earthquake I Feel Love and all hell broke loose. Meanwhile, back in the 1920s, a Soviet physicist and spy, while working on measuring the density of gases, had accidentally invented a new electronic instrument that he named after himself. Leon Theremin’s otherworldly warbler was first toured in classical concerts before becoming a mainstay of 1960s sci-fi film soundtracks.
Radio 3 presenter Elizabeth Alker’s book is a sparkling map of such connections, and it is enlivened by encounters with practitioners including McCartney himself, Jonny Greenwood from Radiohead and DJ the Blessed Madonna. Greenwood names the Polish composer Krzysztof Penderecki as an influence – he was also “very good at drinking vodka late at night” – while the German electronic artist Nils Frahm cites John Cage as inspiration for learning to listen to the spaces between notes. (The female composer Pauline Oliveros, Alker argues persuasively, was a still under-acknowledged influence on Cage and his milieu at that time.) John Cale of the Velvet Underground explains how he was inspired to add viola drones to Lou Reed’s songs as a result of studying with avant garde composer La Monte Young. Young himself proves a spicy interviewee: “When one does music on the level that I do music,” he warns, “it is not entertainment.” He is rumoured, Alker reports, to be able to spend six hours taking a shower.
Wandering through the whole book like a dapper ghost, meanwhile, is Erik Satie, the Parisian prophet of what he called, self-deprecatingly, “furniture music”. He has apparently influenced absolutely everyone, up to and including ambient-techno pioneers the Orb.
Despite this book’s subtitle, of course, it has never been a simple one-way street from classical music to pop. Popular music, in the form of jazz, heavily influenced Stravinsky – and so did the folk tradition. What counts as “classical” music is, too, a matter for debate. Alker praises 20th-century experimenters for working to “free” music from “classical” notions of strict harmony and rhythm, though the idea that those were an oppressive prison is now very old hat. Indeed, she later celebrates composers, such as Terry Riley and Reich, who willingly re-embraced the servitude apparently represented by C-major chords. And the modern “neoclassical” movement represented by Frahm and Ólafur Arnalds, which follows on from Reich’s and Philip Glass’s minimalism, is all about harmony and melody, as well as the kind of relaxing vibe it shares with Japanese ambient electronica, itself the subject of a particularly lovely final chapter.
But this is a book that delights in music and sound of all kinds, and its author has the wit to call the surge in popularity of ambient music a “quiet boom”, so this is merely a quibble. Its guiding principle nestles in a wise line supplied to the author by bassist and record producer Youth (AKA Martin Glover) and then echoed approvingly by Reich himself: “Good music is good music.”
• Everything We Do Is Music: How 20th-Century Classical Music Shaped Pop by Elizabeth Alker is published by Faber (£20). To support the Guardian order your copy at guardianbookshop.com. Delivery charges may apply.
