Crossover settings on a Wiim Amp hooked to a Wharfedale EVO 4.4 and a SVS SB-1000 Sub

[MikeAVR]

Hey guys, I need some help in setting up my new system which consist of a Wiim Amp, Wharfedale EVO 4.4 and a SVS SB-1000 Sub. The EVO 4.4 has a bass extension of (-6dB) 38 Hz. So what sub settings should I use on the Wiim Amp which only has the crossover and db level options? I have set the crossover frequency on the sub to LFE and the volume to 12o'clock (50%). Only listening pleasure, no HT. Any advice would be appreciated.