Phantom power on stereo mic

  • Thread starter Thread starter MaartenC
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moresound said:
I'm pretty sure that you have to have both channel phantom on so that both capsules see phantom.
It's just a guess for I don't own one to tell you for sure but it just makes sense to me, and like RAMI said if it doesn't need it there will be no consequences.
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Yes - It's normal to have both channels powered on a stereo mic.

Some mics will not work at all if both channels are not powered.

You may also find that even if a mic. does work with only one powered, it will not work well enough due to current draw requeirements.

So - power both channels on a stereo mic.
 
RRuskin said:
In a recent presentation by Wes Dooley of AEA, the folks that make upper-crust ribbon mics, he stated that it's not a good idea to have phantom power on mikes that don't need it if they use output transformers. The reason being that the trannies become magnetized, diminishing their performance.
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Phantom power can actually damage a ribbon mic. unless it's specifically designed to take phantom (as many modern ribbons are designed to do).

So be VERY careful with ribbons.

Phantom power has no effect on a normal moving-coil dynamic.
 
Couple of points...

I'm not an electronics person, but given that phantom power is DC, it would be a simple matter to throw in a couple of diodes that would allow phantom power to be taken from either "output", but only from one.

Everything I have read says that you shou,ld not use phantom power with ribbon mics, as it can damage the mic, but...

The other day I saw a post somewhere from someone who wanted to buy a phantom-powered ribbon mic. I thought, "What a Bozo", but in the post the guy linked to several he was interested in, and sure enough, those critters do exist.

I have always heard that phantom power won't hurt dynamic mics, but I've also heard...

Turn off all phantom power before plugging any mic in. Then turn on phantom power only for the mics that actually need it.

BTW: My Digi 003 Rack allows me to turn phantom power on/off on groups of two channels, i.e. 1 and 2, 3 and 4, or both pairs...
 
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RAMI said:
Yeah, I'm sure he knows more than I do, too. On the other hand, there are a lot of experts that indulge in "audio voodoo", swearing that cables should go in a certain direction and all kinds of weird shit like that. This is the first I've ever heard about phantom affecting the performance of a non-phantom mic. While I don't have enough knowledge to dispute it, I'm not going to change what I've been doing because of it either.
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Audio voodoo types usually try to sell you something to address the "bad joob-joob" in the signal chain. Wes did not and does not indulge in that kind of hucksterism. His remarks were an aside to the basic warning against the mix of phantom power and traditional ribbon mics. Not that I ever used phantom on any of my dynamics or ribbons but now I have yet another reason to refrain from the practice.
 
In case some of us are talking about different things, just to be clear.....I wasn't talking about using phantom power on a ribbon. I'm talking about run of the mill dynamics.
 
...we need MSHILARIOUS in here to clear up whether having phantom power with a regular dynamic isn't recommended.
 
RAMI said:
...we need MSHILARIOUS in here to clear up whether having phantom power with a regular dynamic isn't recommended.
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I was just thinking the same thing ... he needs to turn on his PM function!!!!
Lets all yell real loud together HEY JON









:cool:
 
RAMI said:
In case some of us are talking about different things, just to be clear.....I wasn't talking about using phantom power on a ribbon. I'm talking about run of the mill dynamics.
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Understood from the start.
 
bdenton said:
Everything I have read says that you shoul'd not use phantom power with ribbon mics, as it can damage the mic, but...

The other day I saw a post somewhere from someone who wanted to buy a phantom-powered ribbon mic. I thought, "What a Bozo", but in the post the guy linked to several he was interested in, and sure enough, those critters do exist.
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Phantom will damage a traditional ribbon mic. However - ribbons have a very low output level. Some manufacturers are now including dedicated circuitry in the ribbon mic. to match the level to normal condenser mic. levels and this circuitry requires phantom power. So always check *very* carefully before plugging in a ribbon mic.


bdenton said:
I have always heard that phantom power won't hurt dynamic mics,
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This is correct - a correctly wired balanced dynamic mic. just ignors the phantom power.


bdenton said:
but I've also heard...

Turn off all phantom power before plugging any mic in. Then turn on phantom power only for the mics that actually need it.
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This is a bit of an old wives tale. In the BBC they had global phantom power which was on all the time and mics were just plugged in and out at will without any problems.



RAMI said:
In case some of us are talking about different things, just to be clear.....I wasn't talking about using phantom power on a ribbon. I'm talking about run of the mill dynamics.
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Yup, got that. Phantom won't damage a dynamic at all (correctly wired balanced of course).
 
John what if there is a monitor on while plugging in or out a condenser mic while phantom is on or worst on a live PA? that Earth shattering Ka-boom!!!!!









:cool:
 
moresound said:
John what if there is a monitor on while plugging in or out a condenser mic while phantom is on or worst on a live PA? that Earth shattering Ka-boom!!!!!
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That will happen most of the time regardless of phantom power.

You should always cut the monitors/PA (simply pull the master fader down, or hit a mute button, etc.) when you (un)plug anything... Common sense.

You don't know what signal will be coming into the desk when you plug in, so having the system at full tilt is very dangerous.
 
Yet 34 post later ................ :laughings:
Why don't they just listen to the RAMI ;)








:cool:
 
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