Did I fuck up my mic by disconnecting before turning off phantom power?

D

DarinD

New member
Hey!

I am a total beginner of recording music trying to figure out how to record in Ableton Lite. I will describe an event that just happened, with some questions in the end.

I just got a NT2-A microphone (second hand, un-used, 3 years sine purchase).
and a Focusrite 2i4 2nd gen.

It seemed like the DAW was picking up audio from the mic while I was talking, but I couldn't hear anything in my headphone. Fair enough, keep on trying.

Dramatic Event:
In the Audio track on the DAW, I switched "Monitor" from Off to Auto. Then my computer started making a hella noise, which made me panic and disconnected both the USB from the computer and the microphone from the 2i4.

The noise kept going, so I went to figure that out and got it stopped (not exactly sure how).

Going back to trying to hear me from the microphone, I now could only see it pick up audio slightly when whistling. Only when maxing the gain I finally could hear myself.

I searched on internet and found out that it might be caused by disconnecting the mic before turning off phantom power, which I did when panicked (I did understand the meaning of phantom power or what the 48V button was used for).

So, here I am sitting, worried my mic just got broken.

My questions are:

Why can I only hear myself when talking when the Gain is maxed?
Could it be because I pulled the plug when phantom power was on?
Are there any negative consequences?
Is the microphone broken?
What is a solution?

Mucho gracias
 
Hi Darin,
It's not a great idea to pull the mic with phantom power engaged but it's highly unlikely that it flat out broke the mic.
It's possible, but far from conclusive.

If your speakers were turned on when you enabled monitoring then the loud noise was probably feedback, which isn't anything to worry about,
although feedback should stop pretty abruptly if you D/C the interface and/or mic.
If you don't think that's what it was, please describe the noise for us.

Test the chain at various points.
1: Plug in mic, turn off speakers, engage phantom power, turn up gain, and tap the mic grill gently. The peak LED on the 2i2 should blink to let you know you're overloading.
That means the mic works. Don't worry about hearing anything. Just get that red light blinking to prove step 1.

2: With the same settings and that peak light for confirmation, try to get a meter moving in your DAW.
If you can't, there's some routing issue or the DAW isn't speaking to the hardware. Fix before moving on.
Again...forget about hearing yourself. Each step at a time. ;)

3: With 1 + 2 successful, pop your headphones on. Can you hear audio? If not, that's fine. That's where your monitoring options come in.
Some DAWS have different defaults. ProTools won't let me hear unless I'm recording, or unless I enable live monitoring.
We know you have live monitoring option so try that. Also try recording.

As a footnote, I'd avoid whistling to test, unless you're whistling off axis or have great pop filter protection.
It's very easy to be blasting the capsule with direct air and not realise.

I generally tap the grill gently or just speak normally into the mic.
If the mic is across the room, I'll clap.
I do have a vocalist who insists on whistling as hard/loud/strong/close as he can until he hears himself.
He gets the privilege of using my cheap microphones.
 
The Rode is a properly designed microphone - it doesn't care if phantom is switched off with a switch, a software button or having the XLR unplugged. The only difference is how long it takes the 48V to vanish. Using a switch on a mixer or preamp/interface usually ramps the voltage down. A device with a switch per channel usually just cuts the power, and unplugging is instantaneous. Plugging them in while a channel is on and turned up produced a loud pop, as pins 2 and 3 make contact at slightly different times - with mega volume, you might damage the speaker, but not the mic. Plugging in a dynamic that doesn't need phantom also drives people to panic, but I have never had any brand of microphone object. Follow Steenamaroo's advice above.
 
I'd agree with Rob...Never gave it a second thought to shut off the phantom power before unplugging a mic that required voltage. No different than unplugging a lamp from the socket as opposed to shutting it off the light switch. What's there to hurt? Power on power off....

least that's how I see it.

As Steen has instructed it is most likely a routing / software issue that you will need to step by step run down till you have a good signal coming out of the monitors from the mic.
 
I tend to turn the phantom off before disconnecting, but it should not every damage a mic, I do it manly so I don't short the phantom on the device / mixer, and stuff that up.

Alan.
 
Once again, phantom power is being demonized as some monstrously powerful force that will either reach out and destroy microphones or, if you are not super careful bugger the internals of a mixer or AI.

It just ain't so. It is IMPOSSIBLE to "short out" the P juice on an XLR socket because the 48V ALWAYS arrives via two 6k8 resistors. Thus, linking pins 2&3 does FA because there is no net voltage across them. Linking either to pin 1 causes a MAXIMUM of 7mA to flow which is well within the rating of the mixer/6k8s by definition.

The only "danger" with spook juice is if it finds its way to a device not designed to handle it such as a guitar pedal and for that reason it is not a good idea to put mic pre circuits on TRS patch bays. There have also been one or two mic pres where the 48V is left on a TRS line input, a totally crap design and totally unacceptable bean counting (saving a couple of capacitors)

There is the caveat that vintage ribbons should be kept from phantom power but I have never read of an ACTUAL damage report nor an explanation of the mechanism of said damage?

There is a theoretical danger to dynamic mics IF the cables are faulty (get a fekkin' meter and CHECK them !) but again, I am unaware of a specific case.

Lastly, casual "hot plugging" can send massive bangs through monitors and cans. Avoidable with fader drill.

Dave.
 
RFR said:
With a console I've never turned off phantom power. Ever.

No issues. Ever
Click to expand...

Agreed - the BBC used to have studio XLR patch-panels with phantom on all the time and you just plugged / unplugged as required - no problem at all.
 
Steenamaroo said:
Hi Darin,
It's not a great idea to pull the mic with phantom power engaged but it's highly unlikely that it flat out broke the mic.
It's possible, but far from conclusive.

If your speakers were turned on when you enabled monitoring then the loud noise was probably feedback, which isn't anything to worry about,
although feedback should stop pretty abruptly if you D/C the interface and/or mic.
If you don't think that's what it was, please describe the noise for us.

Test the chain at various points.
1: Plug in mic, turn off speakers, engage phantom power, turn up gain, and tap the mic grill gently. The peak LED on the 2i2 should blink to let you know you're overloading.
That means the mic works. Don't worry about hearing anything. Just get that red light blinking to prove step 1.

2: With the same settings and that peak light for confirmation, try to get a meter moving in your DAW.
If you can't, there's some routing issue or the DAW isn't speaking to the hardware. Fix before moving on.
Again...forget about hearing yourself. Each step at a time. ;)

3: With 1 + 2 successful, pop your headphones on. Can you hear audio? If not, that's fine. That's where your monitoring options come in.
Some DAWS have different defaults. ProTools won't let me hear unless I'm recording, or unless I enable live monitoring.
We know you have live monitoring option so try that. Also try recording.

As a footnote, I'd avoid whistling to test, unless you're whistling off axis or have great pop filter protection.
It's very easy to be blasting the capsule with direct air and not realise.

I generally tap the grill gently or just speak normally into the mic.
If the mic is across the room, I'll clap.
I do have a vocalist who insists on whistling as hard/loud/strong/close as he can until he hears himself.
He gets the privilege of using my cheap microphones.
Click to expand...

Thanks for the replies ya'll. It is comforting to hear. I have since managed to record some stuffz so it's obviously not totally broken.

But when I try #1 on what Steenamaroo suggests, the tapping with the finger on the grill causes green light flashes, but not red, when the gain is on ca 7 to max. I can't get red light. Indicating that its not overloading? Maybe if I tap very hard I could but maybe thats not a good idea. That means that the mic isn't as sensitive as it should be? Why is that?

#2 works as well, but again it doesn't go red, only green all the time.
And #3 works as well.

Oh and thanks for the whistling tip.
 
John Willett said:
Agreed - the BBC used to have studio XLR patch-panels with phantom on all the time and you just plugged / unplugged as required - no problem at all.
Click to expand...

In my humble studio I had short xlr cables going from the console to an xlr bay in the wall.
On the control room side there was another bay. You just plugged mics into the wall.

Of course faders were always down, but phantom was always on.
 
DarinD said:
Thanks for the replies ya'll. It is comforting to hear. I have since managed to record some stuffz so it's obviously not totally broken.

But when I try #1 on what Steenamaroo suggests, the tapping with the finger on the grill causes green light flashes, but not red, when the gain is on ca 7 to max. I can't get red light. Indicating that its not overloading? Maybe if I tap very hard I could but maybe thats not a good idea. That means that the mic isn't as sensitive as it should be? Why is that?

#2 works as well, but again it doesn't go red, only green all the time.
And #3 works as well.

Oh and thanks for the whistling tip.
Click to expand...

Nah, don't worry about that.
I would have expected it to overload but the point was just to make sure there was a signal coming in at that first stage.
Some interfaces don't have any indicator lights except for overload, so a good hard tap at max gain would have been the only solid indicator.
If you have green lights, that's even better.

Glad you had some success. :)
 
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