Ipsos Insight has issued new research which shows that 20 per cent of US residents over 12 now own an MP3 player, underlining what a mass market device it has become.

The figure shows a 15 per cent rise in the installed base of digital music users, and is double the level of use revealed in a 2003 survey.

Teenagers account for 50 per cent of all sales, with 30 per cent within US adults between 18-34 owning a player. 13 per cent of adults aged between 35-54 also own a digital music player.

As predicted, iPods lead the field, with teenagers particularly interested in video-capable models. Interestingly, 6 per cent of US residents own more than one player.

Nearly half of music downloaders own a portable MP3 player (48 per cent), and these owners use their devices an average of 12 hours per week. On average, users have 700 songs stored on their portable music device, with 44 per cent of tracks ripped from CD.

Fee-based downloads (25 per cent) and files obtained from file sharing services (19 per cent) are also common sources of content, the research claims.

"Over the past year, the portable MP3 market has really matured, and we are now seeing not just new buyers entering this market, but also growing levels of multiple device ownership indicative of overall category satisfaction and habitualised behaviour," said Matt Kleinschmit, a pice President with Ipsos Insight.

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