[sastley]

I posted previously about purchasing a combination of a Meier StageDAC and a Woo Audio 3, but sadly, budget constraints have bitten me in the rear once again. My budget of $1400 has now been slashed to $600 at the max, and I have started to look at alternatives. Ideally, I would like to maximize the value of my dollar, so I am open to any suggestions, discrete or all in one. I own a pair of HD595s (50ohms), my previous experiences with them include a ZERO DAC/amp (sold due to recurring smell) and a Woo Audio 6 at a meet. I would ideally like the unit(s) I choose to be able to function as a preamp, as I may end up hooking it up to an amp in the future, but it is a significantly less important feature than headphone sound quality. My source is my computer, using optical out, although USB out would likely be an easier option if the sound quality will remain the same.
 
Options I have looked at so far include the NuForce Icon HDP and the Yulong D100. The Icon scares me somewhat, with the volume imbalance issues and some negative reviews involving hissing, especially with low impedence headphones. The D100 only appears to have one review, but it was very favourable, and to be honest, it looks downright fantastic. The RCA outputs on the D100 aren't controlled by the volume knob (they operate at 100% volume, so my stereo receiver's volume knob would finally see some use), although I don't know if the same is true about the NuForce.
 
Thank you all for your suggestions, and once again, I apologize for my poor English (I'm working on it!).

 

[FallenAngel]

Audio-GD Sparrow, most basic version.  Seriously.
 
After that, consider upgrading headphones and moving from there. 

 

[sastley]

Thank you for the suggestion, but I don't believe the Sparrow is what I'm looking for, especially considering the odd preamp out conditions. My headphone upgrade will come at a later date, I'm trying to get the best sound within the budget I have currently without buying upgrades piecemeal.