In the second part of the company report on HEM and Ferrum, company owner Marcin Hamerla is going to introduce his engineers. It is a very young team on whose ingenuity he can rely and trust. During my visit, the development of the next Ferrum model is already running through its final stages.
After having taken a look at the production of the HYPSOS and the OOR, Marcin and I return to the front area of the large production room. Here Marcin introduces me to his engineers. Maksymilian Matuszak, Artur Grdeń and Kamil Kubik are responsible for hardware development and sit on the outside of two large tables, while the head of the development department Paweł Gorgoń and the three software developers Arkadiusz Bochyński, Andrzej Dziwiński and Jarosław Jabłoński sit on the inside of the two tables. During my stay at HEM, there is a lively exchange between all the colleagues. In line with the photo session, colleague Bochyński, called Bochen by everyone, is wearing the T-shirt that his colleagues presented to him at his farewell party a few days ago. The shirt bears the inscription "this -> isBochen();", followed by a code, which holds for a prime example of the family cohesion that prevails at HEM. At the end of the week, the software developer will have his last workday. Feverishly, he and his colleagues are preparing the implementation of the software for the microcontroller of the USB interface intended for the upcoming Ferrum models. Before their colleague will leave HEM, they definitely want to do one more test run, as a farewell gift, so to speak. It is rather unusual that a USB interface like this is not based on standards. On the other hand, a self-developed interface naturally offers much more flexibility and consistency in the development of future devices. The fact that Marcin lets his developers spend their time on this instead of simply buying-in shows how individually the engineers develop and build according to their own ideas and preferences, or are allowed to respectively. Generally speaking, Marcin emphasizes that the most important thing about the company is their employees and their influence on the finished product. Of course, all Ferrum products in the planning are as well based on a market analysis, and there is a rough roadmap of which product types are going to be released and in what order. However, how each product will be technically designed is mainly based on the engineers' assessments, and it's not uncommon for Ferrum that less conventional technologies make their way. At Ferrum, it is important not only to craft high-quality devices, but also to explore new, innovative and creative paths.
In addition to hardware development, software also plays an enormously important role in this context. Here, too, thinking and developing happens to be very modular. The software should be as independent as possible from the hardware. I ask Paweł Gorgoń to explain some details about their software development to me. Ideally, software should lead to more simplicity and user-friendliness. As a good example serves the direct selection of preconfigured voltages for different devices used on the HYPSOS. Also the reaction of the device to different control parameters, which would be extremely complicated to realize by a circuitry, can be performed much better by an effective software. Depending on what and where the software picks off and subsequently processes, it must in any case be ensured that the software does not have a negative impact on the sonic qualities of a device. For this purpose, a three-layer architecture is generally used. Since I don't know much about software development, Paweł tries to simplify the topic as best as possible. Ultimately, the lower layer constitutes the direct interface to the electronics, and here only data is processed for the time being. The second, middle layer, which acts as the logic layer, accesses and interprets the data of the lower layer. The last, i.e. upper layer, contains the graphical user interface, which compiles all the information clearly understandable for the user. The layers operate interdependently from top to bottom, but not vice versa. This way the concept can be adapted relatively quickly to different devices. For example, the data layer "only" needs to be tuned to new interfaces, while the logic layer and the graphical user interface can resume their work unchanged. Conversely, the entire graphical user interface, for example, can be redesigned without having to recreate any data interfaces or interpretation mechanisms. In reality, of course, this process is much more complicated, and the software is tested and optimized over and over again before it is uploaded onto a device prototype for the first time. The risk of errors destroying the entire board or individual components is too high. Then, after the software has been installed for the first time, still further debugging has to be carried out, as it happens to be called in the parlance used by computer sciencists. Various interfaces are available on the boards for this purpose, to which external devices can be connected, which then deliver status messages and datasets to the connected computer. All programming is done in the programming language C++ on a development server. This allows several developers to work on the same software at the same time. Changes are documented in a log and can then be reviewed or commented on by Paweł. If everything is correct, he releases the lines of code and they are permanently anchored in the software. From the development server, the completed software can then be distributed to the technicians, who upload it to the devices in the production process, or even made available to consumers as firmware. Head of Development Paweł is proud of the fact that the HYPSOS software now runs completely bug-free. All in all, it transpires that the basic substance of Ferrum is being consistently built up here. The development work, both on the software and hardware sides, is laying an important foundation stone for the entire product range still to come.
Afore I have already given a decisive indication on Ferrum's soon-to-be-launched model, and a prototype is already to be spotted in the photos. One of them is currently undergoing a test under everyday operating conditions on Marcin's desk. But, there are a lot more ideas under serious discussion. For a headphone amplifier, the output power of the OOR is unusually high, and so it’s obvious that the question occurs what else could be done with this circuitry. A prototype adapter cable intended for supplying power to a USB interface through a HYPSOS, I am already allowed to photograph. Whether it will be launched to the market exactly like this is yet to be approved. Something is going to happen in terms of cables anyway. Marcin wants to enable the production of special connection cables for supplying power to rare connector types through a HYPSOS also for other cable manufacturers. Corresponding preparations in this regard are currently underway. In addition, Marcin reports that a solution for operating several devices of identical voltage on the HYPSOS is already in the starting pits.
After holding many conversations with the employees at HEM and having taken a lot of photos, the forthcoming dinner is a pleasant and quiet transition to end the day. Accompanied by Marcin, Paweł and Maksymilian, Birgit, Dirk and I make our way to a nearby restaurant. Enjoying the excellent appetizer, we talk about our favourite headphones, Head-Related Transfer Function, Harman Target Curve, Dolby Atmos and the like. Whereas outside a storm blusters, Max elucidates to me his thoughts on open loop and closed loop matters. When designing an open loop, i.e. an amplifier without negative feedback, he considers it important to distribute the resulting distortions as evenly as possible across the entire frequency range. In his opinion, distortions are not always to be considered bad in principle - the valve fans among us will now be nodding in appraisal -, but they should just be disseminated as evenly as possible. Furthermore, he complains about the current aggravation in sourcing parts and components. Sometimes he has to single out not only which parts are most suitable, but also which parts are available in large quantities on the market at all. It is also exciting to learn how parts are selected in a result-oriented manner. On paper, for example, an ES9038 converter chip is better-looking. In the finished application, however, there is almost no difference to an ES9028, whose characteristics are known at HEM like the back of their hand. So it’s no wonder that this chip continues to be relied upon. Suddenly the lights go out. The storm has caused a power failure. We continue to talk cheerfully and remain undisturbed. The power outage continues and we realize that we probably have to dispense with the main course. Marcin remains optimistic, while Paweł and Max bridge the waiting time with some cake, which the courteous restaurant employees offer to us. After about an hour, we have to admit defeat and leave the restaurant as the last guests, even though without a main course, but still in a good mood. Since Marcin isn’t far away from home, we already bid farewell to him. We all hope that the next trade fair is coming along shortly and we will meet again soon. Max takes the responsibility to drive Paweł, Birgit, Dirk and me into the city.
The next day we conclude our visit to Warsaw with a walk through Warsaw's beautiful Old Town. Unfortunately, we didn't manage to get this far on the days before. From a distance, we have a good view of the stadium where, under normal circumstances, the Audio Video Show would have taken place in a few weeks. HEM is still on our minds as we intensively discuss the experiences made the previous day. In the traditional café Blikle I finally say goodbye to Birgit and Dirk. They will stay one more night in Warsaw while I already head out for my journey home.
Finally, once again HEM's Ferrum people show up at a glance, listed here with their names.
Back row (from left): Łukasz Jędrzycki, Jarosław Jabłoński, Andrzej Dziwiński, Andrii Matusiv, Paweł Gorgoń, Krzysztof Moshrif, Igor Sosnowski
Middle row (from left): Zbigniew Cieślak, Magdalena Konarska, Rafał Bednarski, Oleksandr Cherviak, Kamil Kubik, Marta Zygmuntowicz, Arkadiusz Sęk, Oleksandr Promovych
Sitting (from left): Arkadiusz Bochyński, Dariusz Grdeń, Dorota Wiejcka, Marcin Hamerla, Maksymilian Matuszak
Not shown on the photo: Artur Grdeń and Wojtek Głowienka