I'm going to buy an Aguilar OBP-3 to control two Bartolini MM style humbuckers (MMX in the bridge position and an MMC in the neck position). Would I be better off supply the power with a single 9V or two 9V's (i.e. 18V)? I've often been told that 18V is always better, but was skeptical. The reason being is that in another custom project that I did using an SD Basslines MM humbucker with an SD preamp, the signal was so incredibly hot on just a 9V power supply that I have to really watch it when I plug into an amp, and have never had successful results with my wireless unit (it seems to overpower the wireless and cause it to distort). So, any help, advice or opinions you could throw my way would be very much appreciated. Thanks in advance!