"Many product ideas come from our customers".

Hermann Helmke goes by "our Gyro Gearloose" at MONACOR. In this interview, he explains how MONACOR creates new products

We visit Hermann Helmke on our company premises. The path leads past storage rooms and production halls. Finally, the door to the company's development area opens. A large desk laden with technical drawings and measuring instruments clearly stands prominent in the room. This is where MONACOR's Hermann Helmke sits and works on new audio gadgets. In a technical discussion, he explains how he turns ideas into market-ready products and what challenges he has to master in the process. A look at the innovative products already enriching the MONACOR range gives an idea of the creativity and technical expertise combined in this room.

How did you come to develop PA technology?


I built speaker systems for myself and my friends when I was a teenager. Initially from speakers from disused radios and televisions; later from kits from electronics mail order companies. The speakers got bigger and the existing amplifiers (e.g. dual turntables with amplifiers) were no longer powerful enough, not even for my hobby requirements. I then turned to electronics magazines (like "Elektor") to learn how to easily build AF power amplifiers.

You say it so easily: build power amplifiers. Was it as easy as that? Did you have all the parts available?

At the time, hybrid amplifier modules were just coming onto the market, so you could build power amplifiers with just a few external components. In the following years, I discovered the electric guitar. I started to build effect devices like fuzzers and reverb units (at that time still with spring reverbs) just as a personal passion.

This decades-long passion has made you a leading product developer with us for years. For example, you invented and developed the TCB-22 from the MONACOR range, a 2-channel audio balancing transformer. What was the process like?

The initial impetus for its development was, for one thing, a desire among many customers for such a device. At that time, we also lacked a tool to quickly check whether supposedly symmetrical inputs of effects units and amplifiers were really symmetrical. There was a signal generator with a symmetrical output on every test station, but that is not very flexible if you also want to test large active speaker systems without having to move all the equipment onto the lab bench.

A classic for every inventor: making a specific everyday situation easier. Have you thought about how you can solve this so that the measurement is faster and more comfortable?


Yes, almost every technician has a smartphone with a headphone output at hand at all times. This is how the idea came about to develop a passive balancing transformer in a stable steel box. It lets you quickly link your smartphone to the balancing transformer input using a 3.5 mm jack cable. A simple XLR cable is the connection between the balancing transformer and the test object. The balancing transformer does not need a source for the power supply.

It actually sounds obvious. Were there any particular challenges or obstacles you had to overcome?

The biggest challenge was to make the balancing transformer as flexible as possible in use. Nevertheless, we didn't want to exceed a certain price limit. That is the difference between pure invention and product development: the latter has to survive on the market and not just solve a problem.

You also developed the SLA-35, a stereo level and impedance converter. Was there a special event or experience that inspired you to do this?


Strictly speaking, the SLA-35 is not a new development, but a further development. It is based on the SLA-48 developed by an earlier colleague. The SLA-48 was developed at the time of the first CD players. Unlike many other audio sources, which had an output level of 100mV to 1V, the effective output level of most CD players was around 2V. As a result, many input amplifiers were overloaded and distorted by clipping. That was the reason to construct a level converter. In order to be able to use the unit as flexibly as possible, it became a level and impedanceconverter. The SLA-35 is therefore a device adapted to our time.

How long did it take you to develop the 2-channel audio balancing transformer and the stereo level and impedance converter?

I developed the 2-channel audio balancing transformer within 2 weeks using a sample board. The SLA-35 took a little longer to get ready for production, despite the existence of circuit diagrams and a predecessor unit:

I wanted to take into account the requirements of as many customers as possible in terms of functions and housing design. The development time was about four weeks.

You mention the requirements for the products again and again. How do you know what they are?

Many suggestions and product ideas come directly from our customers. But there are always product developments that reflect the zeitgeist. For instance, we have been working on audio transmissions via Ethernet for a long time. There were always two major challenges:

  1. The still clearly too high latency between transmitter input and receiver output and

  2. an insufficient number of audio channels to be transmitted due to the low transmission rate of the networks.

How did you solve that for MONACOR?

We tested a lot of audio-over-ethernet systems. Ultimately, it was the DANTE network that convinced us. In the meantime, we have not only distributed bought-in products in this field, but also implemented our own ideas and developed devices such as DADC-144DT and PA-900DT among others.


A product idea must be implemented on the market as quickly and reliably as possible. We can then always implement product improvements in a device update.

Do you plan further products, can you reveal something?

Of course, I can't reveal everything we're planning for the future. But a two-channel balanced version of the EVAB-22 is already in the pipeline.

What are your biggest challenges in general as a product developer in the field of sound system technology?

I have to keep up to date with new electronic chips and other components. There are always new contemporary component developments. With these new components, with the right imagination and technical knowledge, we develop new devices that are not yet on the market. It's a dynamic industry.

How has working as a product developer changed your view of the music and audio industry?


Digital signal processors are increasingly displacing component-intensive analogue and digital effect components. Getting to grips with DSP programming for your own products is essential, since it's a relatively new take on audio engineering.

Would you like to know more about the future of the PA industry? Read our  Interview with Tom Mikus or browse through our Magazine focusing on PA technology.

MONACOR INTERNATIONAL offers a high quality and perfectly adapts products to their target groups. Look on our respective brand website to find out what our product brands got in store for you.