Digital Formats

Wondering if there are any real differences in digital players. For instance I currently run a wadia 170I into a Theta dac. Would there be any real sonic differences in going to a high Rez music player such as the Sony HAP-Z1ES or any of the other music servers currently out?
"11-29-15: 2channeljunkie
There in lies the issue would have to buy the Sony to compare and if no noticeable gain in sound would be stuck to unload the unit.."

That's the nature of the hobby. You listen and compare. To be honest, unless you have issues with your current setup, I don't see the Sony as an upgrade.
Unless the music you want was recorded and processed as hi-res, then I don't see why there would be much advantage in paying more $$ for upsampled redbook quality files. That's not based on any listening tests, but if the information isn't there in the first place, I'm not sure there is any way to reliably predict whether some kind of an algorithm that interpolates what those additional "bits" would sound "better". Take this w a grain of salt, tho, 'cause I have no real understanding of the way these digital products actually work.
I played around with DSD for a while using the Mytek stereo 192 dac. Felt there was really no advantage in sound comparing DSD to redbook except the DSD files were expensive. I sold the Mytek and got an Audionote 2.1b dac and found an Audionote transport used. Playing only redbook it was way better than the Mytek. The Audionote introduced me to multibit dacs which I love. Still have the transport but now have a Audio-GD Master7 dac. Most of my listening is streaming Tidal or Classicsonline from a MacBook Pro. Great great sound and much cheaper than downloading. Also an almost unlimited selection of albums
To answer your question different dacs do sound different
I agree with rodg...
Most of it depends on quality of mastering and recording. The rest is combo of marketing and brainwash.