HD555 (stock) vs HD558 (stock)
- The biggest and most noticeable difference between the HD558 and the HD555 is that the HD558 feels noticeably airier, while the HD555 has a more “closed” sound.
- The HD555 has a more forward upper mid, and while I normally prefer a more engaging upper mid ala the HD555’s. On this case the upper mid can sound glaring on some recordings, whereas the HD558’s upper mid is smoother while still retaining a good presence, though not as engaging as the HD555’s.
- The HD558 has a fuller bass and a more linear extension to the low bass. On the minus side, it is slightly less loose than the HD555’s bass.
- The HD558’s bass has better clarity and texture than the HD555’s.
- Soundstage is noticeably more three dimensional on the HD558, where on the HD555 it’s more left-right soundstage, and smaller as well.
- Ergonomics: the HD558 has a tad more relaxed clamping force, not too big of a difference on short A/B sessions, but more evident on longer sessions. The HD558 cable is also slightly softer and more flexible than the HD555.
HD555 (mod) vs HD558 (mod):
- The HD555 has slightly more emphasis on the upper midrange, which is nice, but at the same time feels thinner at the bottom end. The HD558’s upper mid is slightly less forward than the HD555’s, but both headphones are quite forward in the upper mid.
- The HD558’s is smoother throughout the overall frequency range than the HD555’s.
- The HD558’s bass is fuller and has better extension to the low bass notes. The HD555’s bass is slightly tighter than the HD558’s, where the HD558 can sound a little boomy in the bass.
- Bass punch on the HD555 is slightly punchier, while the HD558 has a weightier bass.
- Soundstage performance of the HD558 is noticeably better, especially in the depth area. A more three dimensional soundstage, versus the left-right soundstage of the HD555.
Overall the HD558 mod is the better headphone, although I do wish that the HD558 (mod) can retain a tighter bass control like on the HD555 (mod).