Phantom Power

That's what I thought. I'd been using this arrangement for some time, but one day the dynamic mic wouldn't work and I tried everything I knew to fix it, but to no avail. I thought that phantom power was the culprit.
 
Under normal circumstances, phantom power won't hurt a dynamic mic. 12 volt phantom power is unusual in pro boards, by the way; 48 volts is standard. I've been using an assortment of dynamic mics on a 48-volt phantom-power board, some of them for over 10 years, with no problems. 12 volts should be less likely to cause problems. The only phantom power problem I've had was when I had to use a 12-volt board - some of my condensers absolutely need 48 volts and won't work on 12.

John
 
The mixer I'm using is a Carvin studio mixer (I know, it does suck). I'm prettey sure it is 12v. The phantom mics are made by either crown or sure. I don't remember off the top of my head. I'll find out.
 
Phanton Power

It is nice to have phantom power selectable on every channel rather than a global phantom power switch on a console. Even if I know that the extra power wont damage the perticular mics I am using, it is always nice to have that control. On smaller consoles it is more rare to see this option, but I do know, that the new Mackie Onyx has this feature, when the previous smaller mackies don't. You can also sometimes buy battery packs to use instead of using phantom power. I know the Audio Technica At853a and the Shure Beta91 can both be purchased with battery packs, and use just a simple 9V battery. I used the battery packs with the Shure Beta91's in 6th grade in additon to phantom power, that was because I had no idea what phantom power was, it just sounded good.

Cheers,
Mike M
 
Our church just got a brand new Allen & Heath PA28... it's gorgeous... It's the first time we've had phantom power per channel, instead of global. I was up on stage playing bass and they couldn't get a signal from my Behringer DI100 (which is an active DI box powered by phantom power)

So, after the song ended, they asked me if I was correctly plugged in. Realizing the issue, I asked them if my channel had phantom power on, they then hit the phantom power button without muting the channel and all the sudden my bass could have been heard in the next county. So, lesson to take away: if you have per channel phantom power, mute or fade the channel down before switching it on or off.
 
avkid said:
unless of course you use cables with loose or frayed wires(obviously)

That would be a sign you need new XLR...desperately!
 
Some CAN be damaged

Yeah it's best to go with the TRS Insert if it's available to you on the dynamics. Electrovoice swears their RE20's can't be damaged by phantom power, but if you listen closely there seems to be a little added noise when run through the powered XLR connect. Then again, it all depends on the board. Just be cautious when you're using the really expensive mics!
 
Phantom power is basicly a + DC voltage present on both pins 2 and 3 with the negative on pin 1. Balanced mice lines are signal on 2 and 3 with ground on pin 1. The equal voltage on 2 and 3 cancel each other out when a balanced dynamic mic is pluged in. There are some old mics and some new really cheep ones around that are unbalaced dynamic and the phantom will fry them (think speaker with DC on it, same thing in the mic but smaller.) The other thing that can be damaged by phantom power is an active out put with a blocking cap with too low of rating. There are some shure WLS units out there with only 30V caps in them that will be damaged by 48V phantom. I suspect some keyboards and bass amps are the same way.
TJB
 
your only phantom power issue is . if you use a ribbon mic generaly used for recording but i know people who use them as overheads for drums insted of cardiods, you will give it far to much power it will completly destroy the mic and ribbon mics are in the $1500.00 and up range so you dont want to pooch one of those. but other wise there is absolutely nothing that phantom power can harm it doesnt matter what you have pluged in aslong as its not a ribbon mic. but if you are a school or a church witha a low budget why would you use extra power when its not necesary leave it off untill you are needing it.

Jon Hirsh
Black Horse Productions
[email protected]
 

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