My first impression is very-very satisfactory. Relax, smooth, natural, flowing, with all the micro detail inside. That’s just sound nice for me – simply my cup of tea. Vocal and mid are impressive, for both man and woman. Be it Ingram Washington or Cai Qin, or drum like Yim Hok Man, are delivered in a very good musicality – especially in detail, separation, and layering. Low frequency is just enough, not too much. High is very detail – a bit too much at first few hours but rapidly improved after 20+ hours, getting smoother but keeping all the details. Sound stage is quite wide (I need a better setup to justify that). I have limitation on experimenting with OpAmps, but I can say this is AD825 with steroid or combination between AD825 + LME49720 (musicality + detail/resolution).
Will wait for the rest 2 pcs to come and wait until they pass at least 50+ hours break-in time.

Full review here: http://jimmyauw.com/2014/11/05/burson-supreme-sound-opamp-4th-generation/#more-3727