Topic: Phantom power with a splitter? Can you do it?

[taper420]

Basically I want to split my mic signal to go into two mixers but I only want to power them with one. Normally I go from the mics to a Samson mixpad 4 into a HiMD. This supplies 18 volts phantom power which is within operating range but not ideal. Now I have a laptop with an XLR USB interface that supplies 48 volt, plus I can record at 24/96. So can I split the XLR coming out of the mics, one into the Samson, one into the USB, and only power it with the USB and still get a signal to both? I'm mostly concerned with having a backup running in case the computer crashes (the recording would stop but the USB power would probably stay on). ....
Upon thinking..
One possiblilty would be to get a battery phantom box and split the signal after it. This would also save on computer power. DOes anybody know how much running 48v on the usb box is eating from my laptop battery? Plus this would enable me to keep a signal live on the HiMD even if  the computer shuts down. Thats the best bet I'm sure, so thats what I'll end up doing....but I still wanna know if I could have done it the other way.

Thanx for the help..

[Steve J]

You should be able to power it with the USB interface. This happens all the time with the sound reinforcement setups. The FOH & monitor engineers work out which board is running power to the mics onstage. Sometimes it's the monitor board, sometimes it FOH board.