Best way to connect Rythmik f12 with Parasound a23+ and Vandersteen 1c's

I recently bought a used Rythmik F12 sub from the goodwill auction site.  I'm wondering if it would be best to utilize the peq and plug in via speaker cables -vandies>sub>parasound or use the parasound a23+'s loop/sub out via rca to sub...anyone have experience running this combo?  

thanks