[Guitarkid]

Thanks, that really helped clear some things up for me. I've always assumed that the 702 was a whole class ahead of the 598s, which I guess was just because of the 702's "classic" status. I've read before about the unnatural sounding upper mid spike you're describing, but I had previously assumed that this was only a shortcoming when compared to reference level cans. Anyway, it was nice to hear someone's observation of how the headphones directly compare. I enjoy the 598's sound signature, so I'm more looking for a step up in quality versus a step sideways in sound signature. I'm listen to a lot of orchestral music (Beethoven, Tchaikovsky, Brahms, Mozart), and I want to hear more detail and clarity in that genre than I currently am with the 598s. I feel too distant and like I'm missing out on some of the music. On the other hand, I really enjoy the 598s for rock music (I worship the Holy Trinity of Led Zeppelin, Pink Floyd, and Jimi Hendrix lol) . I just feel like they have a difficult time reproducing a symphony.
So bottom line is that I can rule out the K702 as a candidate for my next headphone. Based on this thread though it seems the HD 600 could be my ticket