Response from Sennheiser about the 555 mod
The HD 595 is a high-end, open, dynamic stereo headphone with outstanding sound characteristics and excellent wearing comfort. It features Sennheisers innovative E.A.R technology creating a new kind of acoustic experience. Also included is a nifty headphone holder with leatherette nesting bow - the perfect home for your HD 595. If you are seeking a new level of audiophile listening, prepare to be totally amazed by the HD 595 , The HD 555 are using the same driver them HD 595 but headband housing is not the same quality the plastic material will not last the same them HD 595,in conclusion the HD 595 made specifics high end use , who want a better sound quality and a better material quality ."