I started accumulating hearing aids because they looked like
little radios. Before long, I had yet another collection going.
The first ‘electrical’ hearing aids began to appear in the
early 1900s. (Before that, ear trumpets and the like were all people
had to assist hearing.) These early electrical aids are known as
hearing aids for their use of carbon microphones, the
same type microphones that were in early telephones. Carbon microphones
were, in fact, used in telephones well into the 1970s. As you can see
in the Acousticon Model SRD
(1910, USA) above, these hearing aids were
large affairs. What you see held in the hand is just the microphone
part. They also required separate batteries (not shown) that
were heavy and
Amplification was greatly improved with the introduction
vacuum tubes to hearing aids in the 1920s and 1930s. We now think of
this as the transition from ‘electrical’ to ‘electronic.’ The black Western
Electric 125 “Ortho-Tronic”
(1940, USA) shown top center could fit in a pocket but
still required a separate battery pack.
As technologies progressed, both the devices and the batteries required got smaller, eventually allowing a pocket-size hearing aid with self-contained batteries. The early 1950s brought transistors to hearing aids, allowing still smaller devices with single, smaller batteries. By 1956 hearing aids small enough to sit up behind the ear were introduced, and in-ear aids appeared in the 1960s.
Top right: The Beltone Mono-Pac (1947, USA), one of the first with onboard batteries. These pocket sized models used subminiature tubes, generally three of them.
Upper left in the ‘red velvet’ group is the Sonotone 700 (1946, USA) and below that a very attractive underpainted gold Maico (1949, USA). To the right with earphone shown is an Otarion E4 (1946, USA). Below that the clear-cased(!) Zenith 75 (1947, USA) and below that another clear-case model, the Acousticon A-55 (1945, USA). All in this group have self-contained batteries except the Acousticon.
To the left are transistor hearing aids. Far left: Radioear 980 (1967, USA). To the
right of it another Radioear,
this one the 892 (1962, USA). In ivory with the earphone is a Maxitone about which little is
known. Lower left is the tiny chrome Audivox
Petite (1956, USA). This one says on its back “Audivox, Successor to
Western Electric Hearing Aid Div.” The little pocket model in the
middle with the protruding, plug-in microphone is the Zenith Crest (1956, USA). The
behind-the-ear aid in the lower right of this group is a Zenith (c.1970, USA) and the in-ear
aid is a Phonak (c.1990, USA).