Mmmm . . . backstory-fuelled perceptual enhancement!
One of the great comedy stories of recent times has been the ODAC: on a mission to stop anyone spending more than £100 on a 'perfect' DAC “Just As Good As A Benchmark DAC1 - And Here's A Measurement That Proves It!!”.
Trouble is: it doesn't actually sound better than any number of decent sub-£250 commercially-available converters. It's very couth and pleasant, like most of its competitor products, but you need a really good preamp in front of it to get close to interesting.
DACs vary significantly because of their analog stage - their wire-driving 'preamp-ness' - rather more than their digital design - especially in the case of 'front-wheel driven' SPDIF, where the transport will play as big a role as anything in the source. In the case of USB, the DAC's implementation imposes a ceiling on its performance that the computer will to some extent fail to let it reach.
There's a strengthening argument for the integrated DAC/pre, and therefore (like a preamp) choosing the component that best suits your power amplification.
It's very demanding to build a system on the founding premise of analog-domain neutrality - just as it is to build a system using truly low-noise components. It's an ivory-tower, high-end ethos.
For most real-world systems, in typical rooms, running from average mains, with budget constraints - and mindful of listener preferences - a degree of tactical voicing is inevitably desirable.
Which is why, however interesting the measurements are, listening is king. And why there's no substitute for listening in your own system. How many times have you heard a specific component at an audio show, dealer, or mate's place and found it just doesn't work the same at home?
Everything's a tone control, and the buyer is best judge of what works best in his system.
