Players who use a new (0)__E__ of thin-faced titanium drivers to propel the ball further should consider wearing (1) plugs, experts advise. Ear specialists suspect the "sonic boom" the metal club head makes when it strikes the ball damaged the hearing of a 55-year-old golfer they 2) .

They outline the details of this case in the British Medical Journal. The man had been playing with a King Cobra LD titanium club three times a week 3) 18 months and commented that the noise of the club hitting the ball was "like a 4) going off". It had become 5) unpleasant that he decided to stop using the club, but by 6) time he had already suffered some hearing loss.

Doctors at the Norfolk and Norwich University Hospital carried out tests 7) the keen golfer after he attended their clinic with unexplained tinnitus and reduced hearing 8) his right ear. The tests 9) that his hearing problems were typical of 10) seen with exposure to loud noises.

The doctors trawled the web for reviews of the King Cobra LD club and said they found some interesting comments. One player reported: "Drives my mates crazy with that distinctive loud 'BANG' sound." Another said: "This is not so much a ting but a sonic boom which resonates across the course!"

The doctors decided to get a professional golfer to hit shots with six thin-faced titanium clubs from manufacturers 11) as King Cobra, Callaway, Nike and Mizuno. All produced a louder noise 12) standard thicker stainless steel drivers. The worst offender was the Ping G10 at over 130 decibels.