Classical music's reputation for being easier on the ear than its pop and rock relations has taken a knock in a New Zealand studying showing almost two thirds of orchestral musicians suffer hearing loss over the course of their careers.

Massey University researcher Dr Sargunam Sivaraj performed an extensive audiological evaluation of 183 Wellington-based orchestral musicians, testing their hearing, measuring their music exposure and studying the progression of hearing loss over time.

His study found 61 percent of the adult musicians aged 27 to 66 had loss of hearing, while 22 percent of performers aged 18 to 38 suffered diminished hearing, as did 16 percent of child musicians aged 8 to 12.

"Hearing loss is found in all groups of musicians; it is not specific to loud musical instruments or musicians with many years of music exposure," Sivaraj said in a statement.

"But we found the increased years of music exposure causes progressive hearing loss in significant numbers of individual musicians, and this trend is observed in all age groups of musicians but not in all musicians."

Some individuals' hearing loss started at a very early age and gradual deterioration was observed with increased music exposure, while others maintained their hearing despite of extensive music exposure.

"There seems to be large individual variations in initiation and rate of progression of hearing loss."

Female musicians were found to have better hearing thresholds than males, and the progression of hearing loss was slower in females than males.

A national audiology survey had found more than 10 percent of all New Zealanders had some degree of hearing loss, and about a third of all types of hearing loss could be attributed to music and noise exposure, he said.

The research, the first comprehensive study in the world on hearing loss in orchestral musicians, also revealed that although adult and youth musicians were aware of the dangers of repeated exposure to loud music and the benefits of musicians plugs, few used them.

He said musicians should be encouraged to start using musicians plugs at the beginning of their music learning because adaptability to using ear protectors was much better among the children and youth musicians.

He also recommended shorter rehearsals, taking regular breaks, and avoiding rehearsals and performances on the same day.