I had the hd595 for 10 years or something ..held together with tape as the headband cracked then the ear cup broke off so had to send them back to senns a few months ago for the repair at fixed price £54.....sennheiser didn't repair em just sent me a brand new pair of 598 which was nice.... but I didn't like them as much as my old hd595,,, the new hd598 had way too much midrange for me not enough bass ...didn't sound as fun as my old hd595 ( I know with wear buring in long hours would have been better but sold them and bought the hd650 very happy now .
When I 1st got the hd595 I didn't like them preferred my grados so let them burn in for 100s of hours while listensing to other cans....then I fell in love with the 595 ..I miss them... I had the higher ohm version
The hd595 and hd598 sound different