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Best way to combat vocal mic bleed in live scenario?

Discussion in 'Vocals' started by FrostAtronach, Feb 9, 2013.

  1. FrostAtronach

    FrostAtronach Active Member

    Hey there, I play in a 2 person metal band and lately during rehearsals we have run into high bleed on the mic. I'm using a Shure Beta58.
    I have tried multiple positions around the room to eliminate bleed, and so far have reduced it a little If it matters, we use a rectangle room covered in sound paneling, extra sound blocking baffles on one wall (behind drumset) to the left, Guitar amp to the right, with vocals in the middle. We are running one vocal mic (in the middle) to the mixer then to a jbl aeon 300 Pa system. Also i have already gated the microphone to only open when there is loud noise directed right at it.

    Thank you for your help. I have a show tonight duh
  2. bouldersound

    bouldersound Real guitars are for old people. Well-Known Member

    You're probably already doing this, but use relative distance and the polar pattern of the mic to your advantage. Eat the mic and stay on axis, place it so sources of bleed are as far away as possible and in the nulls of the mic (counting reflections). Gates become pretty useless when bleed is close to the same level as the intended source (or higher). Not sure what your "sound paneling" consists of, but more absorption might help. Turning down will help, but that advice always seems to get ignored.
  3. Paul999

    Paul999 Active Member

    Boulder sound has it nailed. When vocalists want to record at the same time as the band in my studio I do try to isolate them but if not I have a scalable sound trap system that includes a window to block most of the bleed out. I always tell the band that the bleed in the vocal mic will determine the volume that the band can play at.
  4. FrostAtronach

    FrostAtronach Active Member

    I assure you turning down was the first thing we tried. Unfortunately there is a limit to how low i can play at so my drummer can hear me. In this setting, the only thing mic'd is vocals so we need to be certain he can hear me. As for eating the mic, i try to do that and am usually spot on. Thanks for your help
  5. FrostAtronach

    FrostAtronach Active Member

    Thank you for your input
  6. RemyRAD

    RemyRAD Well-Known Member

    There is another microphone technique that can eliminate most bleed. It's called a differential microphone. It actually requires a pair of identical microphones. The microphones are taped together/strapped together. You only sing into one. The other microphone is connected to the microphone you are singing in, with an XLR Y cord where one of the two female connectors is wired phase reversed on pins two and three. And it won't pick up any bleed no matter how loud the band gets. Sounds a bit funky as it affects the response of the microphone but hey, no bleed.

    Don't think I'm crazy. This is a technique I've known for a long time. And one I also saw it used that same identical way in a Grateful Dead band documentary. Though Jerry looked like he was singing into Sony lav mics on a special stand adapter and looked a lot like ECM 50's with the metal ball pop filter included with those lav mics. And that's how you obtain virtually zero bleed at any raucous volume level. It was a technique I used with two AKG 414's for an announcer in the lighting booth at the back of the Shakespeare Theater in Washington DC because the lighting booth had no windows for this NBC-TV network special to keep the sound level out of the announcers microphone/microphones. And that worked very well with nary a peep. And it'll work just as well with a pair of 57's. You only sing into one of the two microphones that are closely positioned together. Because it will only output what is NOT common to both channels. Which is why you sing only into one. And it affected frequency response in which you had to compensate for a bit on your program equalizer on your console/mixer. It actually provides for greater presence but less low end and virtually feedback proof. And then you can blow your mates off their socks LOL no problem.

    I have differential feelings about differential microphones but they work. Just the way you need them to.
    Mx. Remy Ann David
  7. Paul999

    Paul999 Active Member

    I always wondered what that was when I saw those videos in the 70's with 2 mics taped together.

    Thanks Remy
  8. RemyRAD

    RemyRAD Well-Known Member

    Yeah, it's a cool thing to do when you absolutely positively need it to work under grossly adverse conditions mostly. It really does not sound like a normal microphone because of the phase cancellation trick that is being performed. But EQ's in the hands of a competent engineer can make it work. Certainly not the best way to go but it is in that application of extreme interference.

    Actually, this technique goes back to the days of noise canceling military style communication microphones on your helmet. How else is anybody going to hear you when you are on the flight deck of an aircraft carrier with a lot of traffic? Aside from a high altitude air flight mask style? On your helmet microphone your mouth is shouting into the front side. And on the back side is the other microphone out of phase to the front you are screaming into. But those were only good for 300-3000 Hz telephone quality. And that's where this technique really sprang from I think? It may have just come from military requirements? I don't know the full story behind who first came up with this? I believe it goes back to my late father's era WWII? As I believe this can also be accomplished with carbon button microphones. Not quite applicable to the finer recording world. Although carbon microphones were once all that there was. The electret permanently polarized capsule condenser microphone was a creation by the Japanese during WWII. And a lot of pilots lost their lives because of those microphones. So microphones can kill. They weren't electrocuted or anything like that. They just stopped working from the humidity they were exhaling. So that was not a good application of condenser microphone technologies. Though it may have been good for the Americans who were flying P 51's? Who were using those nasty carbon button microphones. And all you had to do when someone had trouble understanding your speech was to bang on them. That's why engineers pound their fist first on a piece of equipment to get it to behave and stop all of those little carbon granules from hanging out together. I think I'll have a Schlitz? PBR? Or the great Canadian black stripe and red Carling's?

    I could never get into one of those black velvet dresses. Not pretty. And I don't do heels well. Though I do love wearing my purple velvet tops. It's the bottom I have a problem with. I think I need a high weight filter?

    God bless Jack LaLane Because I sure can't. I look fat.
    Mx. Remy Ann David
  9. bouldersound

    bouldersound Real guitars are for old people. Well-Known Member

    Two mics taped together may have been a PA/recording setup. Remy is referring to a custom mic used during the Wall of Sound era, with a little box about the size of a pack of cigarettes and two little tubes, one over the other, each with a condenser element. You sang into the top element and the bottom one was wired with inverted polarity. That canceled out the bleed but passed the vocal, the "differential" signal between the two mics. I think they were built by Brüel & Kjær.
  10. RemyRAD

    RemyRAD Well-Known Member

    No, those were definitely differential microphones in use. You have to use a very specific microphone technique of which they were exhibiting. For specialty recording applications differential microphones are not offered. They must be constructed by whoever elect to use them. Of course it's possible for the that companies such as DPA may offer a specific ad on to allow a configuration, utilizing a pair of their microphones in a differential application? The ones the Grateful Dead that I saw were also most definitely Sony's. They offered a similar version to that ECM 50, on a small telescoping shaft, similar to a FM transistor radio. Separated by a small woodblock from each other and where the woodblock and the microphone stand adapter of which it was secured to.

    It's generally recommended that Omni directional elements are used to be most effective. It will work with cardioid directional microphones also but the low end gets really funky. It also wasn't all that uncommon to occasionally see a newscaster reporting from the beach of a currently hitting hurricane where you would see the Electro-Voice pair of 635's used in that configuration by those few field guys in the know of that kind of audio technique. Some are real good. Others not so much so. And I think some of those guys used multiple popsicle sticks lashed together as the spacer down the length of the body of the microphone. Which is something you would keep handy in your field audio Kit should the need arise. Though I did not pull one of those out-of-town shifts at a beach hurricane, I was a network audio guy so and I would have something of that nature ready in my arsenal if I had been scheduled for one of those assignments. But I pretty much was kept indoors as a live audio guy. They would send me out and about with crews locally to cover blizzards. Which while it looks really brutal in that weather, after the on-air live bit, we would pile back into the hotel bar. Where we would be heading out with the other newscasters and engineers from the other local stations. Which virtually turned it into an on location party assignment. And where you could stay fairly liquored up to help keep you warm. And it's really difficult to stay outside in that weather if you are not properly first lubricated. I'm not talking about the equipment. And then you'd have to hang out for an additional four hours to do the 11 PM news LOL. We were all in great shape by that time. And when all was said and done, we would go to our hotel rooms because we weren't going anywhere. And basically because you largely couldn't until there has been adequate clearing. And so all your food was comped where you can order lowly gourmet meals delivered to your room. Like I said a tough assignment but somebody has to do it. I just hate it when they don't provide enough shampoo. And you'd think you could expect better from a Hilton or a Four Seasons, Ritz-Carlton? So we would have to empty the liquor cabinet in the room. Makes your hair nice and shiny. Your nose also. And that's about the only thing I miss about doing the news. Everything is only the bad news. But it's so much better when you feel all rosy warm from those piping hot Irish Coffees. And they're only talking about a little snow.

    So far we've dodged a bullet when it comes to the snowfall in the Baltimore-Washington corridor. In 83 we had a blizzard on 23 March, two days after the beginning of spring. And I was stuck at the TV station as the sole audio engineer for over 36 hours before they could get other folks in by 4x4's. And it's kind of a funny weird family like situation when you're all hanging out in the control room all day and your food is being catered in the control rooms. Which is probably why when I purchased my Neve from them and during the restoration process, I found a piece of dried spaghetti in a couple of the faders LOL. I thought it was rather cute and unusual. Obviously from a previous control room marathon.

    Not sure which Neve's faders I preferred setting my coffee upon best? And the beer? Because your food was sitting on that one part of the console you would normally keep your drink on. And I remember a few guys who tried to clean the faders with piping hot coffee. Which I think worked? But the Coca-Cola not so much so. And they never bothered to empty the ashtrays at the bottom of the Penny & Giles faders! Sure they would normal the console up but the rest of their tidiness was like sweeping the dirt under the carpet.

    At least you never saw any half eaten hot dogs lying around. Most engineers seem to consume all food when it is free.
    Mx. Remy Ann David

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