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