I seconded what you two said.
My DT 990 250 Ohm Pro experiences a greater sonic change than my HD 650 does when amp'd with the Polaris. That, however, is a pleasant thing in itself, because the DT 990 is rather screechy, and bright as is well-known. The Polaris artfully tames the can. My impression with this combination has been very positive thus far. The Polaris continues delivering and exceeding expectations. More specifically, I have this sensation that the music becomes more tangible and physical. As opposed to before when sometimes notes simply pass by your ears, with the Polaris the music has some weight to it and becomes tactile. Piano sounds more percussive, and orchestras more vibrant. For the DT 990 I usually have it around mid-high BW, mid Gain, no Attenuation, and low-mid Resistance. I have been trying to play with the output resistance jumpers but couldn't figure out what effect I'm supposed to get, or how it's supposed to work. Anyone cares to educate me on this?
[color=rgba(0, 0, 0, 0.870588)][/color]
[color=rgba(0, 0, 0, 0.870588)][/color]
For my HD 650 I like that the sound does not get overly warm. I have it at high BW and high Gain to complement the warmth and silky attributes of the Polaris. Huge sonic "upgrade" compared to my O2, which I always used to amp the HD 650, but felt the headroom constrained.
The Polaris definitely rocks the bottom end. Very dynamic and very fast. The tube-like sound definitely gets me every time!