For all the basshead junkies here, at what crossover point should a subwoofer be set if it is integrated with the Neat Motive SX2?
I know have set the SX2 to 50 hz with high pass filter and the Kef Kube 10 subw to 50 hz low pass filter. It sounds great but 50 hz was just a guess.
Hope to hear from you.
How are you using a high pass filter for the SX2s? A normal speaker/subwoofer setup in most cases sends the full range signal to both main speakers and sub, with the sub using its built in low pass filter.
I wouldn’t bother with the claptrap. Just connect them up as is using NAC A5 properly terminated. 
The quoted frequency range of the SX2 goes down to 35Hz, and the usual starting point for subwoofer integration is a little higher so that you have a little overlap. So I would start at around 40 to 45Hz, but just use this as a starting point and adjust up or down from there by ear.