I am going to reply to a comment made, well before, by one of the members who said that Wavelength tube DACs didn't provide a big enough bang for the buck.
My personal view is that the biggest bang for the buck is in the first $250-$1,000 one spends and that, in most cases, the bang gets smaller as the price increases.
Neverthelss, I have made a number of steps up and the acquisition of a dedicated Mac and a Wavelength tube Dac (Crimson) would be a lateral step or even a step down price-wise as a substitute for the Audio Note (UK) digital equipment I am currently using and, since computer audio is far from a perfect substitute to a DAC+Transport (separates or in one box), there are a number of other characteristics trade-offs that need to be evaluated, not just the audio.
But the idea of "bang for the buck" does still resonate with me, because if you put me in a corner i would have to admit I am almost as happy with the sound I get from an older Arcam rig CD-192T) that I have in my summer place than my Audio Note CD4.1x.
I don't like the sound of all $8,000 Dacs, but the ones I like the most cost at least that much.