I've got that EXACT setup.
I do it all the time for the 56s.
First you will need an RCA to 1/4 patch cord ->
www.bhphotovideo.com,
and a STEREO 1/4 to 2 Male Mono 1/4 Y Jack -
www.bhphotovideo.com
The way I do it is that I take the Aux Out of the 56S, (because it has a volume control), and use the RCA 1/4 patch cord and route it to the RIGHT (lower section) of Channel (2/3) and Channel (4/5).
That will basically send a SUM MONO mix of the HOUSE or MASTER output to the "RIGHT" side of the Behringer mixer.
Next, take the Stereo 1/4 and 2 Mono Males, and plug the 1/4 TSR part into the Headphone jack of the mixer, then the Mono Male 1/4 plugs into the LEFT (upper section) of Channel (2/3) and Channel (4/5).
That will basically send a SUM MONO mix of your CUE to the "LEFT" side of the Behringer mixer.
Next, plug your headphones into the headphone output of the Behringer.
Now what you have to do is PAN the (2/3) channel to the LEFT, and the (4/5) channel to the right, or whatever way you want to customize the sound in the headphones. It gives you more flexibility than you'd expect, but to be honest, I seem to notice a slight delay compared to the built in split cue of the Realistic mixer...but it's MUCH better than nothing...
Here is a close-up of the Behringer.
www.behringer.com
Make sure NOT to plug EITHER output of the Aux or Headphone output into the OUTPUT of the Behringer by accident....
Trust me on that...
Enjoy!
