I have had both. The biggest difference would be the soundstage. The grado close you in a box compared to the sennies, albeit a very pleasant box. Another thing that I distinctly remember is the great amount of detail the grados. Both have a similar amount of bass, mids are also more alike than different, but the treble on the sennies is rounder and softer. In comfort the HD598 wins hands down as to me they are more comfortable than the much lauded HD600.
2/25/14 at 1:30pm