The History of Rastronics
The
history of Rastronics is the history of Steen Rasmussen. It is also the story of the rapid acceptance
of probe microphone measurements for fitting hearing aids.
Born
in December 1942, Steen B. Rasmussen completed his further education with a
Diploma
in Electric Engineering in 1965 and then did his national service in the Army.
In 1967, he joined the R&D department of Madsen Electronics A/S in Herlev and started work on the first 100% digital clinical audiometer (replacing tubes with silesium transistors). In 1968, Rasmussen was promoted to R&D manager and started work on the next generation of impedance (immittance) devices, the ZO 70.
The
first ABR system
The end of the 1960s saw a close collaboration between Madsen
Electronics, Engineer Scott-Nielsen at Bispebjerg Hospital and Poul Osterhammel at the University Hospital
of Copenhagen (Rigshospitalet) on development of the first commercially available auditory brainstem
response (ABR) measuring computer – the ERA 70 Evoked Response Audiometer, introduced in 1971.
This bulky system revolutionized hearing assessment by providing an objective means of testing that didn’t require the patient’s active participation. Together with middle-ear testing, ABR enabled objective testing of the entire auditory pathway – also on infants and other difficult-to-test patient groups.
The ERA 70 was also unique from a technical point of view in that the digital control unit had been developed by Steen Rasmussen himself in the days before the microprocessor was commercially available. The ERA system Steen designed together with Scott-Nielsen and Osterhammel was shown to the leading electrophysiologist Dr. Hallowell Davis (Central Institute of the Deaf, St. Louis), who in 1979 himself coined the term ABR. Dr. Davis immediately purchased a system and spoke of it enthusiastically at every opportunity (which constituted the best advertising possible and provided Madsen Electronics with a major PR boost).
Over the next few years, Rasmussen continued to work on improving ERA systems (ERA 74), which employed electrodes for stimulation. Unfortunately, the electrodes then available were anything but easy to use, and tended to fall off the patient’s skin. One day on the drive home, he had a bright idea for improving electrode design and this solution was soon patented by Madsen Electronics (1976).
When the company decided to drop electrode production, Rasmussen took over the patent and decided to go into business for himself.
The founding of Rastronics
Backed
by the Technical Industrial Development Fund and with a Saab 99 as collateral for a bank loan, Steen
Rasmussen founded Rastronics ApS in Lynge, Denmark, in 1977.
In addition to clinical electrodes, the energetic inventor developed a number of assistive listening devices (ALDs) for the hearing impaired including alarm and light indicator systems as well as induction coil technology (teleloops).
By 1983, Rastronics had about 20 employees and a 60% market share in Denmark.
Real Ear Measurement (REM)
A new
epoch began in 1981 when the company joined researchers Svend Scott-Nielsen and Henning Birk Nielsen
of Bispebjerg Hospital in a project involving the construction of a computerized probe microphone system
for fitting hearing aids.
As early as 1942, Romanow had written: "A hearing aid can be considered as a sound transmission system which is interposed in the path between the source of sound and the listener’s ear. As such, its performance can be judged by comparing the sound that reaches the ear first through the air path and then through the hearing aid"
Although probe microphone measurements were reported by Filler et al in 1945, reliance on the 2cc coupler for electroacoustic measurement of hearing aid performance steered attention away from this topic. In 1979, Earl Harford, Ph.D. pioneered probe microphone measurements in a clinical setting on more than 500 adult ears. A miniature Knowles microphone was placed in the ear canal between the earmould and the eardrum – unfortunately, this couldn’t be accomplished on smaller ears (although small by 1979 standards, the microphone measured 4 x 5 x 2 mm).
Rasmussen and colleagues combined their expertise in electronics with the availability of slender, flexible silicone tubing to design a system whereby any ear canal could be measured. The silicone tubing was simply attached to the sound opening of a microphone hung about the ear, and then inserted into the ear canal; the earmould could then be put in leaving the tube about 5mm from the eardrum. The method was safe, comfortable, and non-invasive.
What’s more, measurements could be performed in an ordinary office environment without requiring a sound box.
Rastronics ushered in the new age of hearing aid fitting and verification when a prototype system designated CCI-10/1 was exhibited at the UHA meeting held in Travemünde in October 1982. CCI stood for Computer-Controlled instrument.
The following month, the system was demo’d at the Bernafon booth at the ASHA convention in Cincinnati – and was an instant hit. Steen Rasmussen became an overnight celebrity in the audiology community and, to this day, is known as the father of REM. In fact, Rasmussen himself coined the term “real ear”, while others talked about CPM (computerized probe microphone) and "insertion gain".
Steen Rasmussen published the paper "How insertion gain measurement can take the guesswork out of hearing aid fittings" in Hearing Instruments, January 1984.
In the same year, a series of articles about Rastronics and REM appeared in Danish newspapers under the following headlines:
- A revolution in treatment
- New invention gives hope to the hearing impaired
- Export fairy tale began with a Saab
- Quit regular job – now selling to 40 countries
Low
hanging fruit
R&D on the new REM system continued through
1983 and full scale production started in August 1983. Over the next couple of years, hundreds of units
were sold to 56 countries all over the world. By 1985, a handful of competing devices had appeared on
the market, but the “low hanging fruit” had already been picked by Rastronics. In 1984, 160 units were
sold in the USA alone. At approximately $7000 each. The next year, 310 units were sold – and the curve
continued upwards.
This success led to the establishment of subsidiaries in Germany, U.S.A., U.K. and Norway. Rasmussen and his collaborators, Scott-Nielsen and Birk Nielsen, traveled extensively lecturing on the benefits of REM. Rastronics entered a period of rapid expansion, and at the company’s head count peaked in 1988 with about 80 employees worldwide.
Meanwhile, Rastronics continued development and a series of improvements were added to the basic CCI-10 system including color monitor, in situ audiometry in SPL, serial data interface to PC or printer, and much more.
Rastronics also succeeded in spreading the word about REM and hearing aid fitting by means of a series of very successful two-day seminars. Held all over the United States in 1985 and 1986, the Rastronics’ REM Schools featured a Faculty of world famous speakers including James Jerger, Charles Berlin, E. Robert Libby, Jerry Northern, Mead Killion, Jerry Popelka, and Earl Harford.
Surrounded by his Advanced School for Hearing Aid Fitting speakers, Steen Rasmussen stands fourth from left in this photo from 1985.
Portable hearing
aid fitting and verification
In 1987, the Australian Government invited tenders
for 90 stationary and 90 portable REM systems. Winning the tender required rapid development of a new,
portable system. A prototype called the portaREM-20 was presented to Australia’s National Acoustic Laboratories
(NAL) the same year, and the tender was Rastronics’.
The portaREM-20 cemented Rastronics’ position as the leading manufacturer of REM equipment. The system combined all the CCI/10 functionality, including test chamber, speaker, monitor and color printer into one portable unit. It even had an RS232C data interface for connection to a PC.
The
portaREM-20 combined all REM functions in one compact,
elegant and portable cabinet.
Stagnating
sales lead to changes of ownership
However, by 1989, competition in this field
had intensified and, despite the advice of many leading lights in audiology, the growth of REM was stagnating.
And with REM equipment accounting for 90% of the company’s sales, Steen Rasmussen responded positively
to the offer he received from giant Cabot Corp. in 1989. Certainly this offer couldn’t have come at
a better time.
80% of Rastronics’ shares were sold to the American corporation in 1989, and Steen Rasmussen continued as CEO. His wife, Annelise, likewise continued as personnel manager and accountant. Despite the best intentions of both parts, this partnership did not work out. First bits of Rastronics were sold off (Audiotronics in Norway to Danplex and Rastronics GmbH to HORTMANN). Then Steen Rasmussen resigned in March 1991.
In May 1991, Rasmussen sold the rest of his shares in the company, which was then sold to Danplex. The major deal Rastronics had been negotiating with hearing aid manufacturer Starkey was taken over by Danplex. Rastronics’ top R&D expert, Stefan Bengtsson likewise went over to Danplex where he continued to evolve REM instrumentation under the Rastronics brand name.
The wheel turns full circle
In
1999, Danplex was acquired by hearing aid manufacturer GN ReSound and so the Danplex and Rastronics
brands joined Madsen Electronics to form GN ReSound’s “audiologic equipment division” at Taastrup.
All three companies had a lot in common and, more importantly, each shared a history of intensive research and product development in close collaboration with the audiology departments of Danish hospitals. A Danish newspaper back in the 1970s described this kind of partnership under the headline “When doctor and engineer share the same objectives”.
On January 1, 2001, GN ReSound’s "audiologic equipment division" became GN Otometrics and moved into new premises at Dybendalsvaenget.
Steen
Rasmussen continued to create after Rastronics
After leaving the company he founded,
Rasmussen founded another named S.R. Electronics. When the most successful product in the pipeline turned
out to be an acoustic rhinometer developed by Steen Rasmussen, the company changed name to Rhinometrics.
The company was subsequently sold to Danish hearing aid manufacturer Oticon and is now part of Oticon’s audiologic equipment subsidiary, Interacoustics.
Nowadays, Steen Rasmussen is involved with providing support for would-be entrepreneurs in his local community -– and also finds time to play golf. In the summer of 2005, the Rasmussens left their idyllic country house near Lynge (including a small forest and a lake with ducks), and moved to a newly constructed, environment-friendly house near the coast at a famous beauty spot called Karrebæksminde in South Zealand. Naturally, Steen designed the high-tech features of the house himself – they include the use of rainwater for washing, sewage treatment, and a heating system using sunshine and geothermic energy.