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DPA 4099g phantom power plugging/unplugging

Discussion in 'Microphones' started by guitarjazzman, May 5, 2015.

  1. guitarjazzman

    guitarjazzman Active Member

    I have recently purchased a DPA 4099g and would like a definitive answer to whether plugging/unplugging with phantom power on is advisable.

    The reason I ask is that the manual states phantom power should be turned off when plugging/unplugging the microphone. I played a gig with a team of sound man at the weekend and when I asked for the phantom power to be turned off, one of the guys told me that it didn't need to be turned off and all the other microphones using phantom power on the stage have never been a problem with not turning off the phantom power.

    I have been Googling and can't come up with an answer. I obviously don't want to damage my microphone and this situation will keep happening! Other people have said that it 'probably' won't be a problem but 'probably' isn't really an ideal answer!

    Thanks!
     
  2. Kurt Foster

    Kurt Foster Distinguished Member

    that's pure laziness. while i would never plug mics in without turning off the phantom power, it's harder on the console than the mic. i wouldn't worry.
     
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  3. pcrecord

    pcrecord Don't you want the best recording like I do ? Well-Known Member

    Last summer, I was on a gig as audio tech. I prepared everything, mics monitors, calibrated the PA then this guy came with the band to mix the show, I was to do the stage monitors with another mixer. I asked him if he was driving the Phantom power or I would since we were on a split snake, he looked at me like if I was comming from outer space... I just smiled got down on the bord and activated the phantom on the overhead and said, 'nevermind, I got it ! )

    Laziness or inconcience, not all audio tech are built the same !! ;)
     
  4. Boswell

    Boswell Moderator Distinguished Member

    If you plug and unplug any type of microphone that requires phantom power with the PP active and the faders up, you are liable to get a very loud pop, so I think DPA are being cautious in their advice to protect both the PA loudspeakers and the ears of the audience. There's no indication that the microphone itself needs the protection, but it is a general rule that you should do all the microphone plugging with PP turned off.

    The DPA 4099 is a lovely microphone, by the way.
     
  5. guitarjazzman

    guitarjazzman Active Member

    Thanks everyone. Sounds like I am being overcautious, but think I will continue to ask for power off to be on the safe side.

    I am certainly liking the new microphone. I am experimenting with running my archtop to the PA via Avalon U5 for the fatness and DPA 4099g for the acoustic 'zing'. I have always just used my Polytone so early days, but it seems to be working with the new setup.
     
  6. paulears

    paulears Well-Known Member

    There are loads of conventions that make a lot of sense, and plugging any mic into a live channel makes a loud bang, an even louder one when you have the phantom turned on. The same thing happens when any device is connected or disconnected live. Dropping faders, turning phantom off, killing the amps - all that stuff is sensible to do, if you can - but sometimes you either forget, or worse - are told by somebody yelling from 50m away that it's off, and they muted the wrong channel and you still get the bang.

    The good news is that the mic itself doesn't care - at some point power just arrives - the mic isn't bothered if it's applied by plugging in, or somebody presses a button. Most phantom mics do a quick fade up as their preamp powers up. It's what it's plugged into that can make the nasty noises - the mic is safe.
     
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  7. dvdhawk

    dvdhawk Well-Known Member

    That sounds like a really nice set-up! In addition to the "lovely" mic, I like the U5 very much too.

    Maybe Boswell can confirm this, but I believe you'll find the phantom power doesn't switch off the instant you hit the switch. I think it takes some time to dissipate the energy. One of our better AKG or Neumann mics recommended in the manual, that you wait a minute or two to fully power down before unplugging. so I generally hit the switch and then go pack up something else while the power ramps-down. Maybe I'm being over-cautious too, but why risk it? It's the tweeters I'd worry about, so muting the channel is a given.
     
  8. paulears

    paulears Well-Known Member

    What would make them advise that? Some of the heavier current devices have a lag when power is applied before they work properly, but instant removal of the power cannot harm the mics, and on many mixers, the phantom off switch is instant, while others with global power to the mic sockets ramps down when the power supply is switched off. The only unpleasant problem is with a live mic, and cutting the power when it's live, and some of the proper large diaphragm condensers make a weird hissy fizz as the preamps shut down. I've never come across anyone turning power off and leaving them before disconnecting - although this was common with tube equipment where moving hot tubes was considered detrimental to their lifespan, so cooling down was sensible.

    Interesting , this.
     
  9. pcrecord

    pcrecord Don't you want the best recording like I do ? Well-Known Member

    If only you had the Avalon V5 instead, you could deal with the preamp tone and Phantom power yourself !
     
  10. guitarjazzman

    guitarjazzman Active Member

    This seems to be an interesting topic. I discussed this with somebody today and he told me that plugging a microphone in with phantom power on will not harm it, although disconnecting is a different story and phantom power should always be turned off first. I presume he is also talking about the power ramping down?
     
  11. dvdhawk

    dvdhawk Well-Known Member

    In all honesty, I don't believe simply pulling the plug will damage the mic (presuming everything else is working as it should). We'd never given it a second thought for years with no consequences. It was always: mute the channel, and plug/unplug the mic. And again, the muting was mostly to protect the speakers and my ears. But then after reading some cautionary blurb in a manual 20 years ago, I decided to err on the side of safety. I always have other gear to pack up, so it's not much of an inconvenience doing something else first and taking down the condenser mics a couple minutes later.

    I was curious myself as to which manual I'd read that would have contained that warning. Whether accurate or not, it was early-mid 90's, before I was even on the misinformation super highway, so I knew it came from some manufacturer's literature - rather than some internet pissing contest. After checking the manuals for the better mics and pre-amps we had at the time (C414 XLS, TLM193, Focusrite Green Range, etc.), I couldn't find the reference. Then it occurred to me to check the manual of the quite popular, (but quite middlin) mixer we were using at the time.

    Ladies and Gentlemen, I give you this excerpt of page 14 of the Mackie 8-Bus Manual
     

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  12. paulears

    paulears Well-Known Member

    Over protective nonsense, but well intentioned. As for the minute? If you look at the power supply they use in these mixers, and the block switching, there seems no component capable of storing charge that long in the design. I've stuck a meter on all the kit I have handy here, and the longest any of them has taken to drop to zero is just over a second. Most appear to simply switch, and the power is cut instantaneously ( or at least ramps down so quickly it looks like a switch). I think DVDhawk is right, has anyone ever had a mic that suffered from having it's power cut suddenly? Cutting phantom power on some of my mics creates a gradual fade out but this seems to be the capacitors in the mic maintaining operation for a few seconds. We are talking very small current demands here. As said, the biggest problem is the speaker system going crack, so a simple mute solves the problems.

    We are creating a problem where none exists?
     
  13. DonnyThompson

    DonnyThompson Distinguished Member

    I guess it's just become kind of a second nature/habit thing for me over the years to mute channels before connecting or disconnecting anything to a console (or pre), along with not plugging a mic into a channel that is already "hot" with PP.

    To be honest, I can't even recall when or where this habit was actually founded... it's just the way I've always done it.
     
  14. Kurt Foster

    Kurt Foster Distinguished Member

    Mackie must have put that in the manual for some reason .... ? sometimes i wonder what makes you tick Paul....

    probably the first time you plugged or unplugged something and blew a tweeter .... lol.
     
  15. dvdhawk

    dvdhawk Well-Known Member

    In my slightly fuzzy memories, I specifically remembered the words 'ramp' 'down'. I should have known it was a Mackie manual, they always had a knack for keeping the manual as fun and interesting as a manual could be. But in the quest for the right manual online, I used the keywords 'ramp down' along with 'phantom power' and found numerous DIY forum topics involving building specific phantom power ramp-up and ramp-down circuitry (to protect the connected equipment from spikes, more so than the mics). Although one poster claimed his Amek would kill mics with rogue voltage resulting from frequently blown diodes, as well as his Millennia pre-amp - the general consensus was the same as here. Mute it, and make or break the connection - all other things being equal, the mic won't be damaged. I know if we're auditioning different vocal mics, etc. I'm not twiddling my thumbs for a minute or two in between mics.
     
  16. paulears

    paulears Well-Known Member

    Often wonder myself Kurt, but I suspect that much of what goes into manuals nowadays has little basic in electronics or engineering, and more in CYA. The same basic circuit configurations are used on numerous products and supplying power via switches, jack plugs being inserted or battery connectors being snapped on is pretty commonplace. Gently applying power rather than a sudden application is a wonderfully gentle method of starting something up, and letting the capacitors discharge to give a nice slow ramp down is equally kind, but frankly - if a manufacturer designs a product so fragile that it will pop it's clogs if somebody just connects it to my mind is bad design. Some people religiously turn town the knobs on their power amp, before switching off and do the same thing in reverse - yet they now all have such open and closed circuit protection the old surges and trip outs that happened when somebody just flipped on the mains power with a full input applied don't happen any longer.

    I find some of the recommendations in equipment manuals nowadays based on either concerns about shoddy design that could, with the wind in the wrong direction, possibly contribute to some kind of failure. I've lost faith in manufacturers trying to give themselves a get out of jail card.

    On one of my mixers, the position it sits makes it quite awkward to get to the rear panel, and all the XLRs are populated with the ins and outs on a patch bay that can be a easily reached - and this means phantom is on for practically all the channels - controlled from switches on the rear. This means that we must have connected and disconnected thousands of mics over perhaps ten years with no issues whatsoever, and I trust this actual usage fare more than comments on the net. So all the dynamics get phantom, and the only problem is when patching in another mixer - which works fine 95% of the time, and the only snags we occasionally get are a weird warble on the audio, or on some Soundcrafts, perfect audio, but LED meters all pegged to full scale. Only then, will we remove the pile of equipment mounted over the back panel, and turn phantom off.

    I've found no practical issues, and really cannot see any electronic ones. Hence me consigning the manufactures recommendation to the audiophile list of essential practices.
     
  17. Kurt Foster

    Kurt Foster Distinguished Member

    yeah, i have run into that too ... on a Trident no less. doesn't make much sense does it? it would really be a pain if you were using a ribbon mic.

    i always opt to err on the safe side. no matter how difficult, i will always shut down phantom before plugging / unplugging any mic. that's what 2nds and interns are for.
     
  18. paulears

    paulears Well-Known Member

    For something so important, I've never understood why it gets consigned to the rear panels - reinforces my idea that leaving it on isn't as destructive as rumour promotes. Re there actually any ribbons out there that don't use centre tapped transformers, mine do/did, and have never caused me any problems that way. I could, of course just be lucky!

    I've only just noticed that my band PA (using an X32) has the phantom applied to about 25% of the inputs, and we've sort of just developed a system for setting up that is quick - so the audio guy does FOH, while we all cable up the CAT5 to the monitors, the mics and shove plugs into sockets - often at speed. Coloured cable, marked up plugs etc - we can do it pretty quickly, and it's a complex rig now - the only rule we do use is that the x32 master never gets shoved up till the stage end people are happy, but that rule developed purely to save ears more than kit!

    Re: the 2nd/interns, I've discovered that these are more likely than me to observe the 'rules' than me!


    The OP asked for a definitive answer so I guess it's "best practice is to NOT connect with phantom applied to the channel, but if you forget, no harm is done"
     
  19. guitarjazzman

    guitarjazzman Active Member

    Thanks everyone. I feel much happier now that I won't be destroying my new microphone any time soon.... I hope!
     
  20. Davedog

    Davedog Distinguished Member

    There's only one good answer. Better safe than sorry........Its an easy task....turn the phantom on after mic placement....turn it off when clearing the floor........simple......really.....
     

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