Hortmann builds ground-breaking vestibular unit

In 1971, a young engineer established the Hortmann KG in Metzingen, Germany. Working together with ENT doctors and clinics, Günther Hortmann succeeded in developing vestibular equipment to record eye movements as an alternative to the primitive Frenzel lenses being used at the time.

The subsequent introduction of the first Photo-Electric Nystagmograph marked the inception of a long period of success and collaboration in the vestibular and audiology fields.

Danplex is founded in 1972

When Kamplex went out of business in 1971, the former Technical Director Jørgen Jensen purchased some of the assets from the estate, e.g. production equipment and inventory, and founded Danplex in 1972. The rest of the assets were bought by the newly started Interacoustics under Per Honoré.

Moving from Assens to Odense, Danplex began developing advanced, portable audiometers and impedance bridges. The ZA20 impedance bridge was launched with great success in 1973 while 1976 saw the introduction of the first CMOS-based audiometer, the AS50, featuring LEDs and an audiogram pad on the front panel for easy and accurate threshold entry.

However, in 1979, the company was sold to the leading hearing aid manufacturer Rexton of Switzerland. Rexton, in turn, merged the company with Dana Medica, owned by former Danavox sales manager Gunnar Klansø.

Headquartered in Copenhagen, production and R&D were moved in 1981 to Sanderum just outside Odense, and a new era of hectic activity and expansion began.

The early days of ABR

In the early 1970s, Madsen Electronics started working together with another pioneer at Rigshospitalet, Poul Osterhammel, on a new, non-invasive technique for identifying brain tumors called evoked response audiometry (ERA). Naturally, he turned to friend and mentor Poul Madsen for help in constructing hardware for data collection.

This collaboration led to the ERA 74, the world’s first commercially available system for measuring auditory brainstem responses (ABR). Over the next 10 years, Madsen, Osterhammel and Terkildsen toured the world giving talks on evoked response audiometry.

Another landmark occurred in 1971 when, in Toronto, Madsen launched the ZO 70, the impedance bridge that became the workhorse of middle ear diagnostics for many years to come – as well as the device generations of audiologists learned on.