I have tried the E10K and I think with the 6XX it did sound anemic/bright. Compared to the iFi Nano I had back then, the Nano had better bass, mids and a more controlled yet detailed treble than the E10K. Since then I have upgraded to a iFi iDSD signature for portable use and the Hifiman EF400 for desktop use and while they do have their own sound signature, they both do have a very similar overall sonic presentation to the iFi Nano I had back then. So yeah basically I think upgrading to something in the $150-$250 range definitely be an improvement and should give you the proper sound out of the headphones in all frequencies.