I am sure this is a topic that has been covered to some extent but it probably bear5s repeating. I presently have an old velodyne subwoofer. I plan on getting either the new 350 or HSU VTF 2 v 3. If I use both subs in my system how do I go about setting them up. For instance: Do I use the same crossover point.
yes.
How do I adjust the loudness and figure out the phase settings?
This is a generic suggestion because your room acoustics will be unique. But in a typical room I would first start with making sure once again that all your speakers are level balanced at 75db. Lower the subwoofer level at the receiver to -5 to minimize distortion and give you room to raise it. Next set up one sub A on the mid sidewall and adjust level so it is 70db on the rs metre and 0 deg phase. Turn off sub A Then set up the other sub B right beside it so it is colocated follow the same steps above. Now turn oon both subs. Measure combined output. It should be very close to 76db and the subs are working properly. Turn off both subs again.
Then put the other sub B on the opposite sidewall but just off perpendicular, so its not exactly across (the idea being to make it slightly asymetric since I've found its just a bit smoother off that perpendicular axis). Adjust level to 70db again at the new placement. Next set the phase in that sub to 180 deg so the woofers facing each other are moving out of phase. The idea is not to maximize output from reinforcing peaks but to smooth response so there is less volatility on your RS metre. Depending on your room 0 degrees may be smoother (not louder from reinforced peaks). Now turn on both subs and measure output. Depending on how far they are from each other the coupling effect will give you a combined output between 70bd to 76db. At 72.5db the subs output will be level with the speakers. Now adjust the subwoofer level on the receiver to taste, remembering that anything above 72.5 will be running the subs hot. Chill drinks and get the popcorn ready.
