current use is for watching movies / series on netflix on a nexus 7 tablet , though occasional use with a vintage sony 818 mp3 player.   utterly spectacular analog-sounding output  via koss porta-pro´s , which makes a match to rival much more expensive stuff -  at least the porta-pro´s beat my other headphones , namely shure 530 , and sennheiser 280, which despite similar specs sound thin and lifeless , and gary explains why, and i quote him from an email (one of many always courteous, patient, prompt, unfailing) : "The copper wire that is used to...