Well as the original owner of grinch's and apparently dave-the-rave's ZOTL, I didn't have any bass issues in conjunction with the CD3000. IIRC, though, I did feel that with the HD600, the ZOTL was a little too polite and reserved across the spectrum (not just bass). Great if that's the kind of sound you want, but for me, you combine the HD600 "veil" with the ZOTL's politeness and you have some pretty bland sound. Still, it sounded great with the CD3000s.