The oldest piece I still own is a Stax SR-40/SRD-4 set that I got in the '70s. I have upgraded to a SRX Mk 3/ SRM-T1S(pretty vintage, themselves); but I still plug the SR-40s in to the T1S from time to time. They have something in their sound that I will always love. The SRD-4 is in my small system so I can use the SR-40s there, too... In my 1991 Nakamichi Receiver 2.