simple stereo RCA to mono XLR cable build question

Hi, I want to build a couple cables that will allow me to connect the RCA audio outputs of consumer equipment to a single XLR input of an audio console. I want to make these cables so I don't have to use a complex setup including a pair of direct boxes and connectors and adapters and the like.
I am not looking for the perfect solution, but an affordable and streamlined (no clutter!) approach.
I imagine a pair of 10K resistors joining the two hot pins from the RCA outputs to pin 3 of an XLR male connector, and the shields joined directly to pin 1 would do the trick? Would there be a better value of resistor to safely join the two sources?
Thanks for any input!
 
could you draw what you mean?

so you are trying do to mono summing from a stereo source?

First, I don't know why you would use resistors - I don't see any reason? Secondly, usually pin 2 is 'hot' (pin 3 carries the negative going signal), so I would connect the rca pins to pin 2, although it probably doen't matter much if your not an 'absolute phase' fanatic. And, yes, the rca shields would go to pin 1.

You could just build it and see, I doubt you could hurt anything. The only thing I see the resistors doing is attenuating the signals some..