Well. The new amp/DAC combo I purchased really stirred things up a bit. (Gustard H10 + Geek Out 450 for anyone curious)
1: Sansui SS-100: Still as good as it always was, but that last little bit of smearing and cloudiness/lack of coherency to the sound is simply gone. My absolute best and favorite headphone in everything but comfort. Have to set the gain to +6dB on the Gustard for these.
2: Pioneer SE-500 (modified): Gotta say, I'm really surprised with this decrepit old thing. It's the second headphone I ever bought on my own, and it's been through countless repairs and hasn't seen much consistent use in the past couple years. Turns out all it needed was a ludicrous amount of power. It sounds similar to the SS-100 in presentation and timbre: fast, low distortion, deep and coherent if a little 2-dimensional, very clean, and very seductive. There are times when using these that I feel like it actually has more tactility to it than the Sansuis; instruments are easier to pick out and place. It is however, considerably brighter than the SS-100, by virtue of both lack of bass/bass weight and fleshier upper midrange/treble. I find that it sees about the same amount of head time as the SS-100. Still, the lack of ability to hit that last low octave is a critical flaw and makes them difficult to listen to with some tracks. These prefer -6dB gain on the amp, though they gain bass as you feed them current (lower gain; unfortunately the Gustard can't get them loud enough on any setting below -6)
Too tired to type out the others... the only ones worth mentioning are incomplete modding projects anyways.
hope that I will have the same opinion vs LCD 3 (I have auditioned these cans and was very impressed).
