hold on
does your front L/R audio amp have a passthrough? (or a tape/record out?) if so, don't run a splitter (it'll mess with volume control and quality)
anyways, ideally you'd go 1212->power amps -> front L/R passthrough -> headamp
another option is to go with the digital out, but like has been said, the 1212 will have better quality than anything you'll find in a reasonable price range (now if buying something like the Benchmark DAC or something a few bucks down is possible, that'd be a different story, and yes the 1212's digital output should be good enough to keep up with a DAC1 (its ~120db SNR unless you've got a wicked old card in which case idk, I know the one they currently sell, and have sold for ~years is the same base board used in the 1616, which shares its D/A and A/D stages with the ProTools HD racks, so ~120 dB SNR and really low THD/IMD (basically very transpoarent, and basically as transparent as it gets for that price segment (and double or triple that price segment, more $$$ just gives more channels or I/O power)))
anyways, enough of the rambling, lol, look for L/R passthroughs (what amps are you driving off of this? and what cans are you wanting to drive? (if they're relatively low impedance, like Grado or Denon cans, and you've got an amp with a headphone output, you might be able to get good sound just doing that (if they're high impedance, like Sennheiser, AKG, etc you should really run a head-amp))
edit ::
just thought about this, if you get a headamp with a passthrough you could put that between the 1212 and the front L/R amplifier, without cutting up the signal as much as going 1/4 TRS -> twin TRS -> twin RCA out (see how much its getting cut apart?)