Need assistance with Neutrik combo connector and Phantom power
Hey guys, searched the net and got some background but not a definitive answer and thought maybe you guys could help.
I currently have an A&H mixwizard that I use for live shows and have it racked in a mixer rack with it on top and my outboard below. In the back of the rack I installed rack rails and am installing patch bays so I have flexibility. I also want to make a psuedo patch bay for all the inputs outputs to the mixer because getting back there once it's mounted is a REAL PITA.
Here's the issue on the mixwiz mic inputs, if you plug in the 1/4" input it automatically disconnects the XLR input to that channel. So I cannot connect the two at one time and just patch it to one or the other, I would have to permanently choose. Being that every situation can be different, it's not the best solution.
So I came across the Neutrik combo jacks and thought it would work great! I could plug in a 1/4" or XLR and it would just get fed to the XLR input on the mixer.
Then it Dawned on me: PHANTOM POWER that each channel has! I know my dynamics can usually handle it, and currently I don't use ribbons live, BUT when the 1/4" comes into play, WHAT IF a keyboard or guitar gets plugged in while the phantom is on? BOOM right? From what I'm reading it appears it would be a very BAD thing. With 48V on the pos and then ground on the other, I figure that voltage has got to go somewhere, and I don't want to blow the output circuitry of an expensive keyboard. Of course, I could wire this all up and be VERY careful about the phantom being activated, but mistakes DO happen and want to minimize that risk while getting full utility of the mixer.
Any suggestions? Is there any way to wire a Neutrik Combo jack so that the phantom only applies to the XLR and not the 1/4"? I see lots of prosumer gear that seems to handle this but I would bet they have discreet curcuitry in there that handles this routing. Is it a matter of a couple of resistors on the TS pins? It would be too expensive, but am I looking at transformers?