Hey there, been awhile. I'm still looking for a proper upgrade to my HE-4XXs sub $1,000. Better distortion figures, closed or open-back, with a base frequency response that smooths out the treble, and adds a more prevalent bass and midrange response. I had some ideas, HD-650/6XX, LCD-2, or 2C, HE6SE V2, or the Ether CXs. I'd be grateful for any advice or recommendations in that regard. Thanks again :>