Subwoofer connection to Luxman R-117?


Just picked up this receiver and it is everything that people have said  although it has a lot of dated options I do not need; tapes and dubbing).
That said, it makes for newfound joyous musical moments for me.  It makes my ADS 780/2 sing that my old Yamaha RX- 800 was not able to fulfill. That said, I do miss all those digital connections. Luckily my little Schiita phono stage. and Audio Engine B1 also have RCA connections too. I have a paradigm PS 10 Sub want to add but unsure of safest method as to respect the R-117. The sub connection terminates with a 3.5 mm male connection. Do I just buy a 3.5 to a 2 RCA female adapter then run rca cables to ???  The adapters are real cheap but I do not want to compromise a signal or create any damage or havoc to my receiver.  Critical guidance is welcomed.   Also is the phono stage on the R-117 superior to Schiita. I was just avoiding pulling everything back out to get behind all the shelves and equipment. 
just_asking

Showing 1 response by just_asking

Thanks so much for taking the time to offer direct advice and clarification
Full sub model is Paradigm PS1000 v3. 
Upon further inspection I discovered I am  technically inept. I errantly described the cable I explained in original post. The interconnect cable actually is 2 rca male that start at the subs Low Level Input and  Output from sub out, life out or pre out and this 15ft thick insulated cable terminates with a single hefty rca male ( that I used to insert to the dedicated subwoofer out on my old Yam Rx-V800. I appreciate all these options I did realize existed. If I am understanding what you shared above I can take the easy button And insert the single rca male into either of the top pre out??  Or buy the adapter you mentioned as to enable left right info in conjunction with / a set of short rca cables. 
Or just replace the heavy duty cable and use a set of long enough 6 ft) RCA 2 make to 2 male and directly connect the devices. 
I do not think I am ready (yet) for option 2 and any of the three suggested  connections. (as of today) 
my main speakers are the ADS 780/S2 which do not seem to need the sub but I have 3 smaller speaker sets in a closet that would need the sub. Mission 502, B&W 685 (not S2) and Pioneer Elite SP EBS73.