Violectric HPA V550 Pro

While neutral-warm is a good description, I would say it's most noticeable characteristic is it's smoothness. Unfortunately the smoothness hides some of the details, and that is why it is not a stand-alone end game amp and needs to be paired with anther amp. I paired it very well with a WA-6SE that not only fits perfectly and matches V550 in dimensions, design and style, but used as pre-amp for the tube amp produces a very lovely middle ground, giving me a nice selection to pair with a variety of headphones, and this is where V550 can find's it's place in a end-game setup.
My most demanding headphones are an older Arya, that are very hard to drive, and with volume at 10-11:30 and 0db gain, it drives them perfectly, with a very coherent sound stage.
Unfortunately the motorized volume control still has some issues. At times it will refuse to move and you will need to go and manually move the volume knob to make it respond to the remote control. The problem is not bad enough to send it back, but annoying enough to mention it. I want to clarify that the issue should not be a decisive factor in picking this amp or not, it is more an annoyance when happens then a problem.
Conclusion: the amp has a nice sound signature aimed to be pleasing and enjoyable, not to reveal the more finer details in your track, and you don't have to worry about driving every headphone in your collection. My final overall score would be 9/10