I have 2 40.1's and I intend on strapping them since I will be running 6 15's. Now I did some math and I was only able to come up with this for 6 15's, series 6-D1 coils= .5ohm 6-D2 coils= .7ohm parallel 6-D1 coils= .125 6-D2 coils= .167 Someone please correct it if I'm wrong but I dont think I can strap the amps up in either formation.