Input impedance "per leg"?

Hi Guys

I hope you don't mind. I'm not a audio DIYer but you guys are full of knowledge I was hoping you could answer a simple question for me.
I have a pair of active speakers that state the input impedance is 10Kohm per leg. I'm not used to seeing the "per leg". Does per leg mean the input inpedance is actually 10+10 = 20Kohm. I need to know as was hoping to use with a tube pre-amp, they wont work very well is they really are only 10Kohm.

Many Thanks!
Clicked on something, downloaded the manual. Preamp looks like it has balanced outs, should be a shoe-in with just the XLR right cable. Each side +/- gets 10K to ground. If that's too low, you can always go in there and change those resistors to whatever value you like. If you can handle SMD components possibly...