The problem is that the HEV-70 is as bad an amp as the HE-60 is a good headphone. It is a severe, limitation of the HE-60 so if you are listening to the HE-60 through the HEV-70 all you are hearing are the HEV-70s faults not the HE-60s virtues or faults. Anyone who judges the HE-60 only upon hearing it out of the HEV-70 is doing themselves a great disservice. This is not dependent upon what you listened to previously, the HEV-70 sucks 24/7/365.25.