Many people complain that pop music was better in the good old days. Arctic Monkeys and Lily Allen are poor substitutes for the Beatles and Bob Dylan, the argument goes.

Older fans also insist that songs heard through iPods just don’t rock as they used to, compared with the clarity of CDs and the crackling charm of vinyl.

Research has shown, however, that today’s iPod generation prefers the tinnier and flatter sound of digital music, just as previous generations preferred the grainier sounds of vinyl. Computers have made music so easy to obtain that the young no longer appreciate high fidelity, it seems.

The theory has been developed by Jonathan Berger, Professor of Music at Stanford University, California. For the past eight years his students have taken part in an experiment in which they listen to songs in a variety of different forms, including MP3s, a standard format for digital music. “I found not only that MP3s were not thought of as low quality, but over time there was a rise in preference for MP3s,” Professor Berger said.

He suggests that iPods may have changed our perception of music, and that as young people become increasingly familiar with the sound of digital tracks the more they grow to like it.

He compared the phenomenon to the continued preference of some people for music from vinyl records heard through a gramophone. “Some people prefer that needle noise — the noise of little dust particles that create noise in the grooves,” he said. “I think there’s a sense of warmth and comfort in that.”

Music producers complain that the “compression” of some digital music means that the sound quality is poorer than with CDs and other types of recording. Professor Berger says that the digitising process leaves music with a “sizzle” or a metallic sound.

Producers complain that as modern listeners hear their songs through iPods and their computers, music has to become ever-louder to hold their attention. “Now there’s a constant race to be louder than other people’s records,” said Stephen Street, who has produced records for Blur, the Cranberries and Kaiser Chiefs. “What you are hearing is that everything is being squared off and is losing that level of depth and clarity. I’d hate to think that anything I’d slaved over in the studio is only going to be listened to on a bloody iPod.”

Other musicians have said that compression robs a song of its emotional power by reducing the difference between the loudest and softest sounds. Bob Dylan told Rolling Stone magazine recently that modern albums “have sound all over them. There’s no definition of nothing, no vocal, no thing, just like — static.”

Ken Nelson, producer of Coldplay’s first two albums, said: “An example of overcompression is the last Green Day album. If you try listening to it from beginning to end it’s hard work. After three songs you need to put something on that’s been recorded in the 70s.”

Rennie Pilgrem, a dance music producer, said that he mixed his tracks while listening to them through iPod headphones to cater to the less refined tastes of today’s youth. “To my ears iPods are not even as good quality as cassette tape,” he said. “But once someone gets used to that sound then they feel comfortable with it.”

Advances in technology have often resulted in profound changes in the style of popular music. Music historians point to keyboards in the 18th century moving from the plucked string of the harpsichord to the hammered string of the piano. For the first time, composers could devise songs that got progressively louder from note to note, something that was impossible on a harpsichord.

In the early 20th century, the cylinders on Thomas Edison’s phonograph could play recorded music for only four minutes at a time, something that listeners became used to. Today tracks are still generally about four minutes long.

Digital revolution

2001 the first iPod was released

125,000 models were sold in that first year

100 million had been sold by April 2007

30,000 songs (or 150 hours of TV) can be stored on the latest 120GB model

22 grams the weight of an iPod shuffle

Sources: ipodreview.co.uk; ipodhistory.com; Apple

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