Good morning Controlbooth! I had something interesting happen this past weekend at our school's show choir invitational that has me a tad perplexed. I have a set of AT (something-something) boundary microphones that require phantom power. My console is a Midas and has phantom power capabilities... when the tiny switch is engaged on the back of the board. I set up the AT's, plugged them into channel 3 and 4 (which is a hardwired port SL). Tested their sound making sure that everything was ok at the board (including the phantom power being on) and got nothing. I switched the AT's to various hardwired ports around our stage and still got nothing. I then put AA batteries into the AT's pack and voila... they worked. This has never happened before. They have always been able to run off of phantom power without the batteries. My questions: 1. Do they normally require batteries and all of my previous 12 years of experience has been a fluke? 2. Since the wire run from our booth to the stage is very long... (I am estimating by the time the wire tray... our school has all wires; electric, internet, microphone, DMX, etc, running in these "cable trays" in the ceiling that look like rib cages... reaches the ports, there is over a 175' run) ... do you think that there is a voltage drop? 3. Is it possible that the people who installed the system miswired some of the ports (because my hanging microphones which require phantom power DO work when patched into the board through our patch bay). 4. I know that they sell phantom power units. Would that be a worthwhile investment or should I stick with batteries. Thanks! Tenor.