Cloth ears gets a hearing aid

Eight eyes, neatly arranged into four pairs, are boring into the back of my head. The perspiration runs down my back. In front of me is a control desk with 80,000 knobs and some of those slidey things that people in recording studios use. My left hand is attached to one of the knobs, and I switch it from position A to position B (stop me if I'm getting too technical for you here).

I am eyeballed by the eight eyeballs of the four slider sliders. 'Can you hear it?' they ask. 'No,' I say. 'Can you hear it yet?' they ask.

'No,' I say. I'll spare you the next dozen iterations of this. You get the picture. We are in Abbey Road studios listening to two separate versions - let's call them A and B - of that Kate Bush/Peter Gabriel song where they sound like a bad day - the milk's off, it's drizzling outside and the live match on Sky is Southampton v Coventry.

I'm listening to an identifying digital watermark that has been put into one version, enabling a computer to recognise exactly what it is. Or rather, I'm not listening to it, because I can't hear it. Behind me are the boffins from Arbitron, who invented the watermark. They haven't finished it yet, because trained sound engineers, known in the business as golden ears, can still detect it. Even their juniors (silver ears, natch) can hear it. Enid Blyton children's book characters (Big Ears) and 1980s pop duos (Tears for Fears) can sometimes hear watermarks, but only when they take their respective silly hats off.

With or without a hat, I'm officially ranked as cloth ears. 'It's A that has the watermark,' I say, bluffing with confidence. I'm right! Their faces fall. Back to the drawing board.

The boffins are watermarking music for a number of reasons. In the future, we will all be able to download our own music and write it to a compact disc in the shop - there has to be a watermark so that we can trace pirate copies back to their source. They will also be able to log what a radio station plays just by making a computer listen to it all day. So deserving artists like Billy Rae Cyrus will get the right royalty every time Achy Breaky Heart is played.

Watching the faces drop as cloth ears picks out their watermark, you know this is one of the few times in the history of high technology - that's high as in unfinished - when a product will have to work before the developer makes a bean from it. Secure internet payment and internet telephones are two more - where nearly right is no better than wrong.

The following will never happen. You: 'My Kate Bush CD sounds like it's being played underwater.' Technician: 'That's a known feature in this version of watermarking. We'll fix it in the next release.'

This is why developments like watermarking and secure payment will take a lot longer than people thought two years ago. They need 100 per cent customer confidence first, not at all the usual way of doing things. This need for perfection is driving the watermarking programmers crazy. Although listening to Kate Bush constantly can't be helping.

Tim Philips is a freelance IT journalist