I say try it out and see how it sounds to you. If the volume control in the component (doesn't matter what it is) is at fault you should hear it as some difference/degradation in sound quality. I don't think it needs to be more complicated than that (at least initially).
Control volume with DAC or Preamp?
My DAC (PS Audio Directstream) has a volume control and so does my preamp(Benchmark), of course. What’s the best way to control the volume of my system to get optimum sound...turn the dac to maximum volume and use the preamp to make adjustments , turn the preamp to maximum and use the DAC for adjustments, turn each of them up part way? Or does it not make a difference?