At Kanazawa-bunko Station on Keikyu Main Line, I met Keikyu N1000 Series 1017F set, equipping variable-frequency controller sounding like musical scale (FGAB♭CDE♭FG) when the train soon after accelerating from resting condition made by SIEMENS.
SIEMENS' variable-frequency controller used to be equipped by railway cars, such as JR East E501 Series (also sounding descending scale when just before stopping), Keikyu 2100 Series, and part of Keikyu 1000 Series, and make the travel on them enjoyable. However, because of the import products, it took much time to ship parts when the devices got out of order from Germany, the controllers are replaced by ones made in Japan.
By 2015, All of them equipped by E501 Series and Keikyu 2100 Series were finished to replace, and those of Keikyu N1000 Series started to be.