Can anyone who has experience with the following amps enlighten me as to the sonic differences between them? Woo Audio WA5 (fully upgraded) Cavalli Audio Liquid Gold I haven't seen many comparisons. I intend on using them with planar magnetic headphones like the LCD-X and Abyss. The Liquid Gold seems more convenient, since there are no tubes to deal with, but if enough people feel the WA5 has a superior sound (which I know is somewhat subjective), I may steer in that direction...or perhaps eventually get them both! Oh, and if there are other amps you prefer over them, feel free to share the details.