In short, there is no comparison between a PSA PerfectWave (MK I or MK II) DAC and a PSA DirectStream DAC.
The latter, in Audiophile Speak, blows away the former.
There are also significant design and functional differences.
As someone else mentioned, the PerfectWave internals can be swapped out for DirectStream internals. So some confusion regarding the nomenclature on the case work can occur.
If you have listening fatigue with too sharp sounding gear, you definitely will have more of this problem with the old Perfectwave model. It’s more digital sounding in the sense of the word. The newer Directstream Dac is known for it sense of ease and non digital sound, but don’t shortchange in detail and resolution. It will be easier on your ears short of a good analog system.
Thank you everyone for the invaluable input. For some reason, there isn’t as much variety in the reviews/demos available by different reviewers. I feel much more educated on this DirectStream DAC now.