Krell HTS subwoofer set up/connection advice

What is the optimal way to set up the subwoofer for both 2-channel music and HT? Main speakers frequency response = 42Hz - 20KHz.

Please advise, Thanks in advance!!
I have read that if you use the balanced outputs for your amp then you can still run the rca outputs to your sub if you want to sub to work with 2 channel stereo. I wonder if you could hook up the sub output to one input and a front channel to the other so it could work for both 2ch and 5.1. What have you tried already and how do you like the HTS1.
I have not bought a sub yet. I listen to 2-channel music almost 100% and do not see the need to add a sub. If/when I have a sub I would try your suggestion and let you know. I pair the Krell with BAT VK-200 and Taylo Ref. The sound is smooth, detailed.