Phantom Power

  • Thread starter Thread starter ntnguitarist3
  • Start date Start date
N

ntnguitarist3

New member
im almost positive this was asked 30 times but im still alittle confused... alright i have 4 mics, 2 requiring phantom power and my other 2 the SM57 and SM58 not needing phantom power... i wanna use all 4 at the same time on my mixer, will i damage the 2 sure mic's by using phantom power... Please help me, thanks
 
Dynamics (such as your SM58 and 57) are fine with phantom power....just don't plug a ribbon mic in with phantom power on.
 
OneRoomStudios said:
Dynamics (such as your SM58 and 57) are fine with phantom power....just don't plug a ribbon mic in with phantom power on.

Why can't you plug a ribbon mic in with phantom power? Some old wives tale? If your ribbon mic is wired correctly, and your mic lines are wired correctly, you can plug ribbon mics into lines with phantom power all day long with absolutely no adverse effect what so ever. There are even some ribbon mics, like the Royer R-122 and SF-24 that require phantom power to work.
 
Ribbons are fragile. If there is even a tiny short in the cable the ribbon will be fried. So never applying phantom power is a wise, if not absolute, rule.

The Royers are an exception.
 
Make sure phantom power is off before unplugging ANY of the mics.

I use SM5x all the time with other mics that require phantom power. No problems at all, and perfectly OK to do so.
 
Fletcher said:
Why can't you plug a ribbon mic in with phantom power? Some old wives tale? If your ribbon mic is wired correctly, and your mic lines are wired correctly, you can plug ribbon mics into lines with phantom power all day long with absolutely no adverse effect what so ever. There are even some ribbon mics, like the Royer R-122 and SF-24 that require phantom power to work.


Phantom power is, by definition, a voltage that is "unseen" by a circuit. +48V is put on pin 2 and 3. The element (ribbon) "sees" 0 volts. The condensor uses the 48V with respect to pin 1. Since pin 1 is ground (0V), then the active electronics can be powered with 0V across the element (condensor).

The problem is with a cable that has a conductor that is lower, or higher in resistance (whatever causes the condition). If this happens, then the element (ribbon, condensor, dynamic) starts to see a voltage drop. When this happens, the element starts to draw current through it. This can cause the element to burn out like a fuse.

So, if eveything is working properly, the ribbon mic is safe with phantom power on. If there is a problem, then potentially "poof"

These pinouts are usually standard *but* not always! Check your setup if in doubt.
 
Fletcher said:
Why can't you plug a ribbon mic in with phantom power? Some old wives tale? If your ribbon mic is wired correctly, and your mic lines are wired correctly, you can plug ribbon mics into lines with phantom power all day long with absolutely no adverse effect what so ever. There are even some ribbon mics, like the Royer R-122 and SF-24 that require phantom power to work.

I think that's where the story comes from. Some old ribbon mics (and other dynamics) had the transformer center-tap grounded, which grounds the phantom power, and could pass it through the body/capsule causing damage, and could fry the transformer.
And also, wiring hasn't become standardized until fairly recently. Phantom power is standardized, or is supposed to be, under DIN standard 45 596 or IEC standard 268-15A. Pin 2 hot has become accepted, but it wasn't always. Not to mention shoddy construction resulting in a voltage differential at the mic transformer, also potentially causing damage.
I even found an article by Roger Maycock stating that ribbons should never be plugged into a mic input with phantom power applied!
I'm sure all of these and more have contributed to some of the misinformation regarding phantom power and microphones.
 
I don't know if I'd call it misinformation. Sure, as Fletcher pointed out, you could plug a ribbon mic in as long as everything is wired right etc., but are you really going to risk it? It's true that some of the new ribbon mics actually require phantom power, and these may become more popular, but in general I don't feel like I'm misinforming anyone by telling them not to plug a ribbon mic in while phantom power is on...it's just good advice. I'd rather be careful than actidentally destroy a mic that has taken a great chunk of my hard-earned money to buy. Are you all really saying, "well it should be ok and there's only a chance of it destroying you mic, so go ahead"? If so I would caution you on giving newbies bad advice. Not that I'm far removed from a newbie myself, but I certainly wouldn't want to go around thinking that it's ok for me to plug in any mic with phantom power on.
 
Gee Fletcher, I don't think you would advocate hot-plugging a ribbon into a board.
 
OneRoomStudios said:
I don't know if I'd call it misinformation. Sure, as Fletcher pointed out, you could plug a ribbon mic in as long as everything is wired right etc., but are you really going to risk it? It's true that some of the new ribbon mics actually require phantom power, and these may become more popular, but in general I don't feel like I'm misinforming anyone by telling them not to plug a ribbon mic in while phantom power is on...it's just good advice. I'd rather be careful than actidentally destroy a mic that has taken a great chunk of my hard-earned money to buy. Are you all really saying, "well it should be ok and there's only a chance of it destroying you mic, so go ahead"? If so I would caution you on giving newbies bad advice. Not that I'm far removed from a newbie myself, but I certainly wouldn't want to go around thinking that it's ok for me to plug in any mic with phantom power on.

????????????Absolutely not telling anyone to just go ahead. And maybe I should have said confusion, not misinformation. I was trying to reinforce that if conditions are correct, you will have no problems. And shed some light on why people say not to plug ribbons into phantom power. It's not an old wive's tale, but actually has some basis. But, yes, don't take any risks. Find out first.
 
Back
Top