The history of masking as applied to tinnitus must not be confused with the history of masking. Masking, defined as an interference of external sounds upon external sounds, has a long and well established history but the laws and principles which have evolved from those studies do not apply to the masking of tinnitus. Indeed, the masking of tinnitus is sufficiently unique that the term masking is incorrect. Unfortunately, it is too late to change the term now, but it is important that all realize that masking of tinnitus is entirely different from ordinary masking.

The use of masking for relief of tinnitus has been known for a long time. Perhaps the earliest written record is that of Hippocrates, who in 400 B.C. said: ‘Why is it that the buzzing in the ears ceases if one makes a sound? Is it because the greater sound drives out the less?’ (Book 32, paragraph 961-A). Clearly, Hippocrates had tinnitus (we would even guess that he had a noise-type tinnitus of a medium to low pitch) and clearly, he had experienced what we call masking of tinnitus.

Much work has been done on the concept of an ear level masker by Vernon (1977) and others in the U.S.A. The purpose of our small study in the U.K. was to see whether a low priced ‘Universal’ masking instrument would be-of value.

The maskers were manufactured by George Williams Engineering Ltd and distributed through the Royal National Institute for the Deaf at cost price (Hazell, 1977). The R.N.I.D. already supplies a number of environmental aids for hearing impaired people (such as flashing light door bells, baby alarms, etc) and it was not too difficult to add the prototype ear level masker to this list. The maskers retailed at £25. If the masker proved ineffective a full refund was made on return of the masker. Fitting was carried out in some cases at the Tinnitus Clinic held at University College Hospital, London, and in others by regional Audiology Centres. In all cases the names and addresses of those who purchased maskers were retained and all were circulated with questionnaires some three months after purchase of the masker.