State of the art machinery and robots


GN Hearing has production in Denmark in order to be close to R&D and to exploit the synergies between production and R&D for innovation. GN Hearing has kept the very important production of amplifiers and plastic parts in Denmark. The challenge for them has been to keep production costs low, the quality high and still produce in Denmark.


Fully automatic production lines based on the latest technology and more than 30 robots in three production halls. .


GN Hearing has invested more than 10 million EUR in the site on Præstø.


The fully automatic set-up has increased efficiency in the factory by around 300 pct. . 


GN Hearing is a manufacturer of advanced hearing health-care solutions. GN Hearing is a part of GN Group, which besides GN Hearing, consists of the headset manufacturer GN Audio.

GN Hearing is rooted back to 1943 when Mr. Gerd Rosentrand founded the company Danavox. In 1977, GN Store Nord bought Danavox and today the company is called GN Hearing.

Since 1968, first Danavox and now GN Hearing have had production facilities for hearing aids in Præstø. In 2016, the production facility has 80 employees. GN Hearing produces all amplifier components for their hearing aids as well as about 25 pct. of the plastic parts used in their hearing aids. The finished amplifiers and plastic parts are shipped to China and Malaysia where they are assembled into hearing aids. The factory also has external consumers such as Cochlear etc. 

Keeping production in Denmark and securing innovation

Increased competition on the hearing aid market has pushed many companies into outsourcing production to low salary countries. GN Hearing also has production in China and Malaysia, but kept an important part of the production in Præstø. The company is a well-known industry innovator and was, for instance, among the first hearing aid manufacturers to develop well-functioning apps for its products. GN Hearing also introduced ”Made for iPhone” hearing aids connectable to an iPhone.

In order to stimulate innovation, GN Hearing continuously works on developing a structure that supports this. One of the most important aspects of obtaining innovation at GN Hearing, is to keep a proximity between the company’s R&D department in Copenhagen and the production facilities in order to be able to develop ideas fast.

“There are two main reasons why GN Hearing has chosen to invest heavily in our factory in Præstø; first of all, we are able to make the production highly efficient. Secondly, Præstø has a strong impact on our ability to be innovative e.g. the importance of having close cooperation between the company’s development department and the factory. In a technical advanced company like ours, there has to be ongoing collaboration between the factory and the development department throughout the development process”

- Bjørn Strømboe Petersen,
Senior Vice President, Global Operations, GN Hearing

Also, having production of amplifiers and central plastic parts in Denmark makes it easier for GN Hearing to ensure that those products do not get copied abroad. The challenge however was to find a way to produce the amplifiers in Denmark at a competitive price.

The tool for securing relatively low production costs in a country with high wages has been automation, education and management.


Automatic in-line production

Since 2009, robots and automatic in-line production has been a highly important part of production in Præstø. The first robot at the facilities was a flexible robot from Universal Robots, and since then, more robots have been added. 

The set-up secures efficient production with relatively few employees on the plant floor and illuminates product errors, which in combination helps lower production costs. In Præstø, a large proportion of the production of amplifiers is done in-line without any human interaction.

“Here at the factory in Præstø, we use robotics in order to obtain the highest degree of accuracy and precision in relation to the often very small high-tech products that we produce. In order to produce with extreme accuracy we use different types of robots. In this production facility we have an in-line set-up, where we run 8-10 process steps in-line and where no humans are involved in the actual production (out of a total of 20-25 steps in order to build an amplifier ed.)”.

- Morten Andersen,
Director of Component Mfg, NPI Projects Hybrid, GN Hearing

At the facilities in Præstø, GN Hearing has three production halls - two producing amplifiers and producing sophisticated plastic parts.

The two electronic production halls have a total of five production lines and have recently received its fifth Universal Robot. Furthermore, the production halls have a test robot from Adept and several other machines in the two production halls, including ASM machines (formerly known as Siemens Electronics Assembly). Many of the machines in the assembly lines are placement solutions, with the purpose of placing components on printed circuit boards with a high accuracy.

In the plastic production hall, GN Hearing has a total of 18 robots, most of which are Sepro robots from the French manufacturer Sepro-Group. One more injection-moulding machine will arrive in November and a new two-component machine will arrive in Q1 in 2017.

The latest addition to the production halls will be added in the next few months (2016), when a new Manufacturing Execution System (MES) will be implemented. The MES system will make it possible for GN Hearing to track and document the transformation process from raw materials to finished amplifiers and plastic units. MES software provides data that will help GN Hearing understand how current conditions on the plant floor can be optimized to improve production output.

It is important to underline that the whole set-up and in-line production line is an individually designed process. Skilled GN Hearing engineers have needed to ensure that the different machines in the production line, such as solder machines and pick-and-place machines, could work together and are efficient enough to fulfil the company’s goals. GN Hering also use a MES system for getting data from R&D and very easy get the files into the production computers.

Manufacturing Execution System (MES)

MES system is a computer system that provides information and documentation from the manufacturing plant floor and therefore, helps companies understand how they can optimize production and thereby the finished product.

Using data in improving products and production

GN Hearing has focused on obtaining and using data in order to improve production and products. With the acquisition of the MES system, GN Hearing expects that their access to data and the amount of data collected will increase, and improvements in production can be carried out much earlier in the process.

 “GN Hearing collects data in order have the highest degree of quality e.g. to be able to locate errors quickly, identify the root cause and be able to respond quickly and - thereby improving the efficiency and quality of the product. It is expensive innovative components that we work with (hearing aids ed.) and errors in production must be solved quickly.”

- Bjørn Strømboe Petersen
Senior Vice President, Global Operations, GN Hearing

Up until now, operators have collected data manually from the test machines and optic vision systems but when the MES system is fully integrated in the Præstø facility, most of the data collection will happen automatically and more data will be collected. According to GN Hearing, access to new data will help them improve their processes and in the end, create better products.  If, for instance the quality of the soldering in the amplifiers do not meet a certain quality, this will be discovered quickly and solved so that the entire production is not put at risk.

The results: Improving profitability

According to Bjørn Strømboe Petersen, Senior Vice President, Global Operations at GN Hearing, the team behind the Præstø factory has performed tremendously and has been able fulfill the goals for all GN Hearing production facilities, which is to be 5 % better, faster and cheaper every year.

“The reason why we have chosen to invest heavily in the factory in Præstø is first and foremost because it make sense from an efficiency and innovation perspective. As a responsible company we always look at the costs to produce various parts in the world and because of the fantastic job the team in Præstø has made to streamline and improve production efficiency, Præstø is the best place in the world to have the factory.”

- Bjørn Strømboe Petersen
Senior Vice President, Global Operations, GN Hearing

The results speak for themselves, Bjørn states. Due to the set-up at the factory and dedicated employees, the efficiency at the factory has increased by 300 pct. during the years. While there has been a rise in the number of employees of 15 pct. over the last five years.

Automation and digitalization has also helped improve the yield rate (failure rate ed.), which is now at almost zero. Improvement of yield rate is an important factor in the production of hearing aids where even small production failures can have large consequences for the final product.