Should you turn off phantom power of Focusrite Scarlett to mics when not using them?

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audiophile23496

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Should you turn off phantom power of Focusrite Scarlett to mics when not using them? I have my computer on basically the whole day with my Focusrite Scarlett USB audio interface connected to my computer. Should I turn off the phantom power to my shotgun mics/other mics when not using them? I can see the signal indicator go on and off as I do other things (instead of recording into my mic).

Will it do any harm to my mic (Sennheiser MKH 416 + others) if I leave them on indefinitely? What is the life of a shotgun mic and does leaving them on with phantom power on affect them in any way?

Thank you.
 
I think we're probably talking about barely measurable impacts.
I guess most would say if you're not going to be using them for several hours it would do no harm to turn phantom off.
On the other hand someone might say that regularly cycling power is more likely to strain components over time.

In the long run, I don't imagine you or the microphones will last long enough to really find out.

It's not unlike the computer debate - Shutdown and startup daily, or leave it on and let it sleep?
 
Generally, you're suppose to turn off the phantom power before disconnecting a condenser mic. Also many manufacturer suggest that you connect the mic and then turn on the phantom power. That's how it's been in just about every studio I've worked at...for the past 20 years.
 
I turn it off (or try to remember to) just because I'll sometimes have a random thought to try something and want to grab a mic cable that's handy, often plugged in to an existing mic. So when I yank it out, per [MENTION=197812]SAM CA[/MENTION]'s comment, I've read enough times it's better if the power's off. Of course, I have forgotten because I thought I was going to do another take, and something interrupted and a day or two later it's still on, and I haven't fried anything yet, but the vast majority of the time it's off when I'm not planning to use it the same day.

I suppose to be sure you should read all documentationi for your own particular microphones and interface/preamp and see what they say. If they're silent on the subject you can assume it's not a "should" at least.
 
Managing the phantom power is more a safety issue for certain mics as well as speakers and monitors (loud pop). It's not so much to protect the phantom power source itself, as we're only talking 48v or less.
 
I actually checked all my mics documentation and a few others and did not find any that said phantom power should be turned off at any point! Only Blue microphones (which I don't have) had a detailed list of steps for connecting a mic, which had phantom power being turned on after the mic was connected.

Most of the concern I read posted was actually about potential damage to monitors caused by a loud pop during the disconnect/connect, and just recommended turning the microphone gain down before these operations.

And, FWIW, I didn't read anything anywhere in current documents about harm from keeping power on, with moisture/humidity being the chief concern.
 
It's a practice that is designed simply because of the loud crack that happens when you plug one up with the channel on and open. There's no electrical reason to turn off phantom before connecting a mic. If you mute the channel or pull the fader down, that's good enough. However, some studios do do it as a rule, and with rules, they're somebody else's and if it's their studio, you follow their rules. I have never ever switched things off as a matter of course and all my big mixers have it turned on permanently no matter what is plugged into them. If occasionally you find a device that objects - like Soundcraft mixers when used as submixers, they often light the LEDs up like a christmas tree when their output has 48V on it - it has never caused any harm, just surprise. An Allen and Heath used to produce a weird warble rather than the LED thing.
 
Let me put it this way. Hot plugging a mic is NOT the best way of handing a mic/preamp/monitor set up...period! I'm pretty sure most mics and preamps can deal with this just fine but just to be sure it won't hurt to get into the habit of doing it the right way, especially if you're going to patch a mic through a patchbay. This way you don't have to worry about a nasty thumb, manufacturer suggestion, make and model....etc.
 
Chaps, I think both of your stances are valid but the OP isn't asking about plugging/unplugging.

He seems more concerned about the ill effects, if any, of leaving a microphone powered long-term.
 
Steenamaroo said:
Chaps, I think both of your stances are valid but the OP isn't asking about plugging/unplugging.

He seems more concerned about the ill effects, if any, of leaving a microphone powered long-term.
Click to expand...
Well, thought I covered that, but I didn't read anything, in any of the microphone documents (ones I own and a couple others) about that practice.
 
IDK about y'all, but with my mic pres, there's a pop just turning on the phantom power, so turning it on and off before plugging doesn't really help.

I usually turn mine off mostly because I plug all kinds of pedals and keyboards and other things into those inputs. All of those devices will be have a capacitor in series, and that cap 1) Is probably polarized and expecting the "outside" to be less positive than the "inside" at all times, but the inside is probably idling at less than 48V, and that can make electrolytic caps explode; and B) Probably aren't rated anywhere near 48V anyway. High voltage coupling caps tend to be expensive and large, and most manufacturers spec them just big enough to safely handle what they are trying to squeeze through them but not much else. It's very common - especially in guitar pedals - for them to be 15-18V which is not enough whether they're polarized or not.
 
On my board any condenser mics that are always hooked up to the same inputs(acoustic guitar and most of my drum mics) I leave the phantom on. With my 2i2 for remote tracking, since I regularly change mics I have a habit of turning PP off. For what its worth ,IMOH it doesn't make enough difference in the actual life of the electronics or mics whether you leave it on or shut it off, though I was taught to "burn in" condensers for 24 hours like a speaker or amp( I don't know if it helps but it aint never hurt, plus I've found defective mics very quickly by doing it) I would just go with whichever way is most convenient for your work routine.
 
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