Using two devices with phantom power?

  • Thread starter Thread starter ZoSo58LP
  • Start date Start date
ZoSo58LP

ZoSo58LP

rock guy
Hey guys, so when i use my samson 8 track channel mixer, it has phantom power on it. i need to use said phantom power for my one condenser mic, so i have it turned on. however, i like to use my ART Tube MP preamp, which also has phantom power (but it's turned off, because it's being used for a dynamic mic) but whenever i use it with the mixer, theres a horrible buzz from that track. this is because phantom power on the mixer is ON. once i turn the mixer off, theres no buzz from the preamp, but then i can't use my condenser. and no, i can't use my condenser on my tube preamp using IT'S phantom power, bc my condenser is the stereo MXL vm63, and there's stereo left/right XLR out's from a special cable, and the preamp only has 1 input. any thoughts as to why this buzzes, and is there a way around this so i can use my preamp with it? i mainly use it to get 8 tracks for drums here (because two channels are 1/4 inch input only, so i run hte XLR to the tube preamp, then a 1/4 inch out to the mixer, then i can mic every tom)

please help! we're starting to record a rough demo
 
Two phantom powers from two different sources is bad ju-ju you can only have one on at a time or you'll end up with what you have going on ZoSo.
 
It sounds like you are plugging your ART pre-amp into a mic. input and it does not like the phantom power going into it.

Does it have a line level output? If so, plug it into the line-in of the mixer and the problem should stop.

Otherwise you will need to make up a short XLR lead with blocking capacitors in to stop the phantom power going any further.

Neutrik do little custom boxes that you can use to build this in if you want.

I hope this helps.
 
hey john, thanks for the info. by line-in on the mixer, you mean a quarter inch input? for the preamp, i'm sending it into one of the two tracks that don't have XLR; they only have a quarter inch in. power can't go through quarter inch cables, only XLR, right? this is what i don't understand; why would i still get the buzz if no power is going to it?
 
If you are going run the ART with the mixer...the mic goes to the ART, the ART's Line Out goes to the mixer's Line In...NOT preamp/mic input. (It might be the same connector for both on the mixer, and you have to press a switch on the mixer to change that channel from Mic to Line).

Then you can run phantom on the mixer without it affecting the ART because phantom power is only sent to the mixer's preamp/mic inputs.

If after all that you still have buzz...then it could be some kind of ground loop Ju-Ju...call a witch doctor and start looking for the cause of ground loop. You may need to perform an exorcism to get rid of it. ;)
 
do you have the mixer and the preamp powered from the same wall outlet?
If you have one on one side of the room and the other across the room and therefore plugged into a different outlet, that could cause a groundloop.
 
miroslav, that's what i'm doing actually. i'm not using it on one of the XLR ports, i'm using it on one of the two line in only ports on the right. here's the webpage for the mixer:
Samson Audio - MDR1064

and bob, i've got them powered from the same outlet.
 
You must log in or register to reply here.
Back
Top