It has been a busy day and although it is well after office hours I am still working. I just squeezed out a bit of time to try out the Fostex HP-P1 - SR71A - LCD2 combo, switching between Filters 1 and 2.
Filter 1 of the Fostex HP-P1 is more natural but a bit grainy in the mid range. Filter 2 is more refined but sounds a bit more artificial. Filter 2 has a bit better imaging but human voice is a bit more backward than Filter 1. I think the DAC chip of the Fostex needs some burn-in, but so far I think Filter 1 is my favourite.
Then I connected the same SR71A to the CLAS, volume matched. Brighter, wider soundstage, lower mids sound less grainy than Filter 1 of the Fostex. Suitable for those who want a cleaner sound - but to me this now sounds a bit too clinical / analytical after listening to the HP-P1 -> SR71A combo.
Next, I tried driving the LCD2 the stock amp in the Fostex. It is quite unengaging and unable to drive the lower bass as good as the dedicated amps even at high gain.
Overall, I would say the Fostex with SR71A is a better match for the LCD2 Rev 1. Simply more musical and emotional. But if you are looking for the Rev 2 kind of sound from the Rev 1, the CLAS with SR71A seems to be a better choice. I will test out my ES5 tomorrow as I've still got work tonight.
I am not able to compare the two DAC units using the Stepdance, as the Fostex -> Stepdance combo creates some unwanted noise. Not sure how it happens but the noise just appears with this very combo and not any other combination. But suffice to say that my previous favorite combo, namely the CLAS -> Stepdance combo, is now less preferred by me as far as the LCD2 is concerned.