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Audio Primate has been watching Sony with interest after having a listen to the WM1Z and WM1A at Canjam London 2017 and having a listen to their latest Walkman, the ZX300 at the Indulgence show earlier this year. I’m personally a big fan of the 4.4mm balanced standard. I’ve found that the ubiquitous 2.5mm Astell & Kern style plugs are frail. The only question for me about 4.4mm is how quickly can Sony get other manufacturers to use it and how thin can a device be with the 4.4mm jack. If Sony can build the devices with little to no thickness penalty, as it seems they have with the more lean ZX300 then I think the chances of their success will be good. I’m not consulting the tea leaves just yet, but I predict good fortune.