Tried the line out for the first time with a Graham Slee Voyager amd I am pleasantly surprised.....it is actually a major improvement in all aspects with all of my headphones but outstandingly so with the PS500.
Have the RS1i and the PS500 and absolutely prefer the PS500.
Reason why is the above mentioned bass hump and less treble.Because you have more bass the sound seems to be more grounded and complete.
Also, the PS500 has a more holographic or 3D sound.
I use them with a Fiio X5 or with a Bottlehead Crack with speedball/ Metrum Octave DAC and there is a good synergy with both but obviously the latter is better.
Thanks for quoting my old post and yes, the Lorenz is a good tube and I alternated it with the Sophia.
But as it is a very old post I have sold the Woo in the meantime and have a Bottlehead Crack with Speedball now.
Sorry, to jump in here but I think that the HD800 are worth the price considering they are an engineering masterpiece.
Whereas the RS1i are more "stone age" but funnily enough I prefer them over the HD800.
As often stated before and elsewhere, they are just more fun and let me enjoy the music the way I like it most.