As Bitflipper just said, surround has been possible in SONAR for years. So assuming the OP is not aware of the feature (more on this in a moment), here is how you do it.
 
First assign surround outputs from your interface in Preferences. Then insert a surround bus. After that any audio track can be assigned to the surround bus and instead of a pan control you get a cool little knob that can be controlled with a joystick. Lots of fun if you have a surround monitor system. But exporting to a commercial surround format requires acquiring a license AFAIK. 
 
Unless you are scoring for film there just is no demand for surround formatted music. However if you just want to cover the live version of "Run Like Hell" in the comfort of your home studio, I can say from experience it is worth the effort.
 
One other thing for the OP,
 
Please, learn to use paragraphs.

Sonar has had Surround capability for sometime now, but I would like to see it advanced... This is what I'm looking for it to support the psychoacoustic surround tech seen below! I want to mix in object based surround on any good stereo studio headset!

Native support for Dolby Atmos for Headphones and DTS Headphone:X encoding and playback

 

That would be pretty cool, but have you looked into what it costs to license the Atmos encoder? I don't know, either, but I'm guessing it's VERY expensive. It also requires special equipment for playback, including a hardware decoder or software equivalent, plus, ideally, additional speakers. And it's just one of several competing technologies, so it could easily become a historical footnote along with quadraphonic headphones.
 

bitflipper
Nobody here does it, ...

Actually, some do. I've done a number of mixes in surround in Sonar. I have a surround setup in my studio and 5 speakers + sub in my living room. It's the only way to get full enjoyment out of movies - and additional enjoyment out of 5.1 mixes (like Aero by Jean Michelle Jarre).
 
KEv

bitflipper
That would be pretty cool, but have you looked into what it costs to license the Atmos encoder? I don't know, either, but I'm guessing it's VERY expensive. It also requires special equipment for playback, including a hardware decoder or software equivalent, plus, ideally, additional speakers. And it's just one of several competing technologies, so it could easily become a historical footnote along with quadraphonic headphones.

I have checked into it, but really there's seemingly only one way to create Atmos audio right now, The Dolby Atmos Renderer which, according to Dolby, 'receives audio and metadata from Pro Tools and creates multichannel speaker outputs, binaural headphone outputs, and channel-based deliverables.'
 
The same seems true of DTS:X DTS:X® Creator Suite also designed to work with Pro Tools AAX only. Both quite expensive! Yet they're both not quite what I'm asking for... I'd like to create for DTS Headphone X and Atmos for Headphones.
 
Maybe I still need a better understanding of it, but it seems there should be a way to create DTS Headphone X and Atmos for Headphones without the need of special surround hardware as each of these are not quite the same thing as DTS:X or Dolby Atmos... and can both be experienced from any pair of stereo headsets or even stereo earbuds! I've heard both and both are pretty amazing!
 
With that thought in mind, it'd be nice to see some sort of deal made where we could get versions of these tools which focus on DTS Headphone X and Atmos for Headphones.
 
As I understand it thus far, the audio for both still needs to be encoded accordingly but does not need to be directed to discrete hardware output channels as their counterparts DTS:X or Dolby Atmos do. This is because their effect is, as I mentioned before, psychoacoustic.

Thanks everybody... I now know how to set up a surround bus, mix and assign a device... I just want a minimalist monitoring system that isn't "fake" What about a focusrite scarlet 18i6 or 18i8 and a pair of bluedio victory 12 driver headphones using optical I/o from phones into the scarlet interface?
Feedback anyone?

Only thing that should come out the rear speakers is the sound of the front speakers bouncing off the rear wall... you may not even need speakers for that