wow you are starving your HE-560's...they like power. If you drive them with a good powerful amp, you will be amazed by the sound they produce. I own He-6 that are powered by a parasound a21 amplifier, and powering my He-560's with AudioGD NFB 28 amp I am 85% in the He-6 territory. Earlier in this thread I posted a white paper by Texas Instruments detailing how resistance, frequency, and power can play a role in what you hear from your speakers / headphones. If you are in the MN area, I can lend you my amp for a few hours, and see if you notice a difference. The only pairing that I couldn't stand with my He-560 was with Schiit Lyr (v1.0), not sure why but my He-560 sounded tubby, bloated, and full of harshness with that amp, I am probably an outlier as many others love that pairing. I did enjoy my DT990 paired with the Lyr.