- Some w. sm. signs of wear, but mostly in very good condition.
= Broad collection of different ear trumpets representing the history of acoustic ear trumpets between 1800 and 1900. These acoustic ear trumpets are tubular or funnel-shaped devices which collect sound waves and lead them into the ear. They serve as hearing aids, resulting in a strengthening of the sound energy impact to the eardrum and thus a better hearing for a deaf or hard-of-hearing individual. By the late 18th century, their use was becoming increasingly common. Collapsible conical ear trumpets were made by instrument makers on for specific clients. Toward the late 19th century, hidden hearing aids became increasingly popular. Besides the big, visible ear trumpets, manufacturers began to make smaller devices like 'acoustic headbands', where the hearing aid device was artfully concealed within the hair or headgear. These were made in a variety of shapes that incorporated sound collectors near the ear that would amplify the acoustics. Hearing aids were also hidden in couches, clothing, and accessories. This drive toward ever increasing invisibility was often more about hiding the individual's disability from the public than about helping the individual cope with his problem. This collection comprises: 1. 3 "London Dome" ear trumpets (two brass/ metal, one tortoise celluloid). The name of this type of trumpet comes from its similarity in shape to the dome of St. Pauls Cathedral in London. The design is a parabolic reflector that directs the sound into the ear tube. This achieves considerable gain while maintaining a small size. 2. Three brass and two metal "Guye" ear trumpets, after the Dutch proffesor A.A.G. Guye. This telescopic horn is mostly made of metal and was also used during World War I to intercept the enemy over great distances. 3. Five conversation tubes (black/ tortoise celluloid) which are different from the other ear trumpets because unlike ear trumpets that could pick up sound from distance, conversation tubes were designed to pick up sounds directly from the speaker's mouth. Besides that, it was double effective because the speaker was forced to speak loudly because it was visible that the hearer was having badly hearing. Later conversation tubes were also hidden in chairs. 4. Four ear trumpets after Siebenmann (one brass, two black celluloid and one tortoise celluloid) and two metal andone copper straight telescopic horns. 5. Five auricals, all tortoise celluloid. Liebermann trumpets are impressive in their ability to improve speech understanding in noise due to the boost in high frequencies through the resonance of the narrow tube leading to the ear. Besides that, people had their hands free while listing. Surprisingly enough, acoustic hearing aids did not die out completely with the invention of more modern hearing aid technologies. In fact, they were manufactured right up to around 1990. SEE ILLUSTRATION PLATE CII.