This WES is really giving my HE60 some balls, and the Jade almost have too much bass but it's fun. It's weird that the O2 Mk1 sound better with the WES than any of my previous amps, but on the WES my HE60 and Jade get closer to the O2 and maybe even better than the O2 in soundstage. With the WES the Jade sound more like an O2 with extra bass and extra treble, and a bigger soundstage than my GES could ever give them. They sound good at low, medium or loud volumes.
Switching from the HD800/ZDT to the O2/WES makes it more obvious just how much smaller the O2 soundstage is. It's just not as wide and big and deep and spacious on the O2, but the HE60 are right up there with the best now. The WES changes the airy etherial spacious but un-grounded sound of the HE60 into one that is both spacious and grounded, due to more solid bass impact and presence. But, while more spacious the imaging is not as well focused as the others. The HE60 seems to be best suited to moderate volume levels, not too quiet or too loud.
The O2 Mk1 still excel at quiet music listening, as every little detail is still extracted and the bass doesn't seem rolled off at low volumes, but as I turn up the volume the mids can seem a little warm and full and forward and the bass kicks in harder, but the highs don't fill in quite as well and don't quite keep up with the rest. So, I am going to try my slightly brighter PS Audio Digital Link III DAC with the O2 tomorrow.
On the other hand, the HE60 still seem to get a little too bright at high volumes as the bass doesn't scale up as well at very high levels, and I suspect they could be more fatiguing at higher the moderate volumes. In this sense, the O2 or Jade are a better choice at high volumes. Either way, I am so glad I didn't accept an offer this summer to sell my HE60.