I am looking for the answer and appears that buying them at $36 will be the solution to find out if they sound the same as my 681b or 681f or the 681 (681 cannot be purchased in mainland China at this time).
I will let you guys know in a few weeks when they arrive.
Well they arrived and they sound very good on the SL spectrum. They are burning in but first impressions are that they are the 681 Burgundy NOT the 681b.
I will compare them in a weeks time.
The HD7's appear to be an OEM of the 681 Burgundy Red Ring Classic Version 1.0. They sound better than the 668B and better than the 681F and 681B. The 681x have a more balanced, recessed and reticent soundstage. More delicate. The HD7 more up front, more harmonic compleatness to instruments, vocals are more full-bodied and present and move half a step forward.
Possibly the best sounding can in the original SL OEM Clones and original SL line, excluding the 681 Nulls which I cannot find. That is why I got the HD7. No 681 in my country.Edited by marone - 3/2/14 at 7:02am