subwoofer amp with crossover/phase control


looking to power my Edgar Subwoofer,  like to know if any members know which amp has built in crossover for subwoofer control.   It has to have a phase control.  Please advise?  
128x128zipost
There are two things I would pay someone to help me with:
1) properly setting up my JL Audio F112 v2...I don't understand phase and slope.
2) setting up my speakers 

Post removed 

Actually @jackd, you have it backwards. Brian Ding of Rythmik Audio designed the patented Direct Servo-Feedback circuit and amplifier found in the Rythmik plate amps, and has those plate amps manufactured in China. They all come into the U.S. through Rythmik, Brian then sending Danny Richie of GR Research some to sell with his sub kits.

Danny was already offering a sub kit when he learned of Brian and his new Servo-Feedback design. It occurred to Danny that Brian’s S-F circuit combined with Danny’s idea for an OB/Dipole sub would produce a new state-of-the-art sub. They got together (both are located in Texas) and came up with the finished design of an OB/Dipole sub, as well as some sub drivers. Brian offers complete subs (sealed and ported) and the OB/Dipole Sub kit, Danny DIY sub (sealed and the OB/Dipole) kits only, as well as many loudspeaker kits.

@ricred1  
 
The slope is to match the roll-off of your speakers. Ported and passive radiator speakers roll-off at 24dB/oct, sealed speakers at 12dB/oct.  
 
After finding what frequency you want to cross over at (80Hz for instance), next you find the phase; play a sine wave at the frequency you cross over at, you can find clips on YouTube or on websites (like this one), and adjust your phase/polarity until it registers the loudest in the seating area (so it requires two people or leaving a SPL meter in your seating area), you want the loudest as that’s when the phase is alligned, any misallignment causes a reduction in output, and fully opposite in phase completely negates the sound.