Received my hd 688b n 681 today.
actually only interested with 688b after little bit reading the review on the net but order 681 from trio out of curiosity
Testing my hd 688b with listening 3 album non stop -
Metallica S&M, Epica - Consign to Oblivion (Symphonic metal) and Scorpions - Moment of Glory (with Berlin Orchestra). all flac
directly connect to laptop without dac or amp. somehow my nokia n900 cannot drive this thing.

this headphone stuck on my head nearly for 4 hour. lol

Craving for more bass. I wonder if bass sound could increase if properly amped.

The other headphone can I access currently just Portapro, Beats by dre and Razer Orca.
only recently started this hobby, dunno how to compare but
I like the 668b sound better than razor orca. the good thing about orca is i can use it directly with my nokia n900.
portapro n beats i thinks in different category.


not yet open the 681. maybe tomorow....

second that
After tested both unit outl of box, I think I like 681 more than 668b due to 668b lack of bass. put back 668b on the box and leave it to eat dust on my closet. may open again if i have proper amp and dac to play with. waiting for 681 finish burning in. 1 week to go....