Wish I knew, but I don't. I would think a little higher though, as they probably only use a single-pole filter and thus wouldn't get much attenuation below 100Hz (6dB per octave). I'd guess between 200-400Hz.
Makes sense. I know I like it much better with the x-over on. IMO it takes the "mush" out of the low end and works really well with my set up. For me this is a great chorus pedal over all. Plus, take into account the price and it's just a no brainer.