Lots of good suggestions already - enough to keep you busy for a while. But, frankly, ignore those claims that you should ignore an entire class of DACS (Delta Sigma). If someone wants to suggest that a particular brand doesn't execute their DAC well, that's perfectly reasonable. That likely happens in every category, whether DS, R2R, etc. But to suggest an entire category, and all manufacturers and models within that category, should be ignored is over-generalization and crazy talk.