Well, some thoughts about my SOLO/RX II.
My impression at the moment is shockingly pleased. I've been a RWA imod user for some time and have hundreds of hours experience on 801, and some experience with the colorfly C4. Compare with my imod/RX system, the sound from solo is instantly airier and the sound stage is considerably larger and deeper. Listening to some of my favourate old tracks from the solo is like listen to some thing new, never before have I experienced the details and ambience of the music like this on a portable package! The extension of the highs is so effortless; the mid is so juicy and raw; and the bass, although is slight less in quantity, but so much deeper and bouncier and revealed much more details than the imod and even the 801. the tonal balance and clarity across the frequency is truly stunning.
Over all, IMHO, I prefer the SOLO over imod or C4 or 801, for SOLO is very musical but not creamy like 801, full of details and great high extensions yet juicier than C4. To me, although imod/801/C4 are all master pieces and great in lots of ways, the SOLO is more natural and balanced.
One thing the potential buyer should be aware of is that, the HM801 can be used as a USB DAC/DAC, and C4 has digital input (without LO though) as well, but the SOLO can not be used as a DAC and can only be used with apple i devices.
These are the thoughts for now.
Sorry, I made a big typo! Please see the red part and I don't know what I was thinking when I wrote C4 instead of SOLO.
Edited by Jian - 3/6/11 at 2:08am