The actor Timothy West, a former sound engineer

He is one of our biggest thespians. The son of actors, he is also the husband and father of actors (Prunella Scales and Sam West). Yet after his A-levels, he saw himself purely as an amateur thespian. In the spirit of Noel Coward's song, "Don't Put Your Daughter on the Stage, Mrs Worthington", he advised himself not to give up the day job.

Unfortunately, he didn't have a day job. Even the Army had rejected him, on medical grounds, from the call-up for National Service. But he did find gainful employment in the West End, on the premises of Partridge & Cooper, leading purveyors of office furniture in Holborn, where he helped to look after the showroom. He was far from overworked, as this was mainly a mail-order business.

"I don't think that Partridge & Cooper thought that selling office furniture was ever going to appeal to me for a lifetime, but they were very nice people," he says, looking back at his brief period among the filing cabinets and tubular chairs.

The nice people were right. Pretty soon he was applying for another job, as quality control engineer in the new recorded tapes department of EMI. It was nice work and he got it: listening to music all day. "I have no actual musical education," he admits, "but I love classical music and was given some music tests."

He became the long-stop or final monitor of the music progressing from musicians to customers' ears. "We listened to tapes already spliced together by someone else," he says. "In a big opera, you might have a soloist in the Abbey Road studios and the horns in La Scala, Milan. You had to check the balance of the vocals to the instrumentals and notice if there was any kind of woolliness or if the string tones sounded a bit stodgy or glassy.

"In particular, you had to watch out for the stereo, which had just been introduced: did the trombone section suddenly march from left to right? It was not unusual to find the tenor, just now locked in an embrace with a soprano, suddenly abandoning her for a baritone on the other side of the stage."

The tapes in question had not evolved into today's narrow version, but were a sort of missing link between LPs and Walkman-style cassettes. "We were dealing with quarter-inch tapes running at seven-and-a-half inches per second," says West. "They had the advantage of no needle noise, but were quite cumbersome and could snap." Finally it was his patience which snapped. He became a dogsbody and bit-part actor at the Wimbledon Theatre. It was a case of: Do Put Yourself on the Stage, Master Worthington. The part of sound engineer was no longer being played by Timothy West.

Timothy West appears in the forthcoming BBC1 adaptation of Dickens' 'Bleak House' and is co-author with Prunella Scales of 'So You Want to be An Actor?', published by Nick Hern Books, £9.99