Can I use my SSP's DAC instead of external DAC with Mac Mini?


Didn't see this answered anywhere, and I read the Audioquest primer, but still have questions. I have a nice home theater setup - Classe SSP-600 preprocessor, CA-5200 (5x200W) amp and all B&W Matrix S2 speakers. I'd like to buy / create a digital music server, but I'm unsure whether I can use the SSP's DAC (preferred) OR whether I need to add an external DAC.

The Mac Mini has HDMI, Thunderbolt, and USB 3.0 ports, and a micro-optical headphone jack. The SSP does not have USB or Firewire inputs. I have SPDIF inputs on the SSP and Optical inputs - but don't know whether I can cable direct or need the DAC in between. I'd prefer as few components as possible, and have had a hard time discerning whether they make cables to go from the Mini to Optical or SPDIF, and which would be the best choice. I'd appreciate some help. 

celt16
I believe, if using the DAC within your AVR is preferable, then a USB/SPDIF is your best option going from the MAC mini. One option is an M2Tech HiFace, no need for a USB cable. They come up often on Ebay or AG for under $100. Please keep in mind that any USB DAC has a USB/SPDIF interface contained within. The 1st device the signal passes through therein.  
Forgot to add, wishing you the best with whatever route you chose.
Merry Christmas.
Thanks all for input, and Merry Christmas. Was planning on buying the $499 Mac Mini with 500 MB 5400 RPM drive plus $100 memory upgrade to 8GB, but then I found a refurb Mac Mini with 1TB fusion drive and 16GB for $700 - gonna try the mini-Toslink to Toslink without an external dac for now and see how it sounds. 

mesch - can you expand on your last comment -  "if using the DAC within your AVR is preferable, then a USB/SPDIF is your best option going from the MAC mini" --  better than the straight mini-toslink to toslink cable, and if so why?

mbaudio02 - thanks for info and Clemetine tip - will take a look. 
So the micro-optical headphone jack outputs SPDIF.  I guess I missed that point. Sorry for my confusion.