Electronics-centric video explaining the sound made by the Siemens drive components in the Keikyu N1000 series. These have been replaced with Toyo Denki equipment in refurbished N1000 cars, and more recent batches of the model have had the Toyo parts from new. This YouTube channel is DENKI OTAKU and he has a lot of videos which will interest you if you're into electronics.
Has English overdub.