I do know someone here with a Woo, so my next object is to see if I can manage a 'borrow' of it for desktop listening and testing.
The WA6 is one of those amps that does not distort at the amp level with JH13pro, and brings them up to a whole new level over the portable amps (noted in my review). The Single Power Square Wave XL is another amp that does quite well with the JH13Pro, and brings them to a whole new level above the portable amps.
The sound is quite well controlled with these two amps, and they even reign in the UE11Pro and control them very well. The frequency response also seems to be more even with these two amps, whether it is the ES3X, JH13Pro, or UE11Pro. Somehow the WA6 and Sq Wave XL make all three IEM, each with very different sound signatures, perform at very high levels; and they perform much closer to each other than when they were driven with iPods and portable amps.