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Old January 18th, 2004, 11:56 AM   #1
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bad advice from a pro re lav. Arrgh

I'm doing my best to understand how to identify the right equipment, and sound is particularly difficult for me to understand. I've got J Rose book, etc. I needed a lav for interviews. I had already screwed up early on by buying a battery operated lav with a 60' cord plugged directly in camera via miniplug. Hiss-city.

Bought XLR pro adapter and went to Guitar Center and was shown an AT PRO 7a, mini cardoid fixed charge condenser mic. It ran on a battery, but the salesguy said I also need phantom power. What's the battery for? I ask him. Just so it goes on, he says. I buy the rolls PB23 12/48v Phantom pwr supply, xlr cable, the lav.

I set it up to try it out and I'm thinking, man! This is a lot of cord and connections just to do an interview! Lav to phantom power, phantom power to xlr adaptor, xlr adapter to camera!

This morning I actually sit down with the PRO 7a literature. It says: The Pro 7a is designed for battery use only, and should not be used with phantom power.

1) I already used it with phantom power. did I ruin it?
2) Is there ANYONE I can trust?
3) The pro 7a is an electrect. Rose says externally-polarized condensers are better. Example of ext pol lav?
4) dif b/t mics that use or do not use phantom power?

Thanks

Diane
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Old January 18th, 2004, 12:57 PM   #2
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Trust me, you can always believe us <GGGGG>. Well, some of the time anyway.

1 Phantom power is just that. Unless the microphone is built to use Phantom power, it shouldn't even see it. But the best proof is to use it in a test.

2 See my opening paragraph.

3 Externally polarized microphones are better, so I understand, because the external charge on the membrane can be higher than a residual charge that cannot be renewed. More voltage means a higher level signal out of the element. A higher level signal means that it doesn't need as much amplification which should cut noise levels and the higher voltage out gives a better S/N ratio from the element itself.

4 Can of worms sort of. Some microphones will accept either a battery or Phantom supply. Frequently, if you examing the microphone specifications, you will see that they perform slightly better with Phantom power (it's a higher voltage usually).

That said, Sony lavs like the ECM-44 won't accept Phantom power and they sound pretty good for voice. The ME2 lav that came with my Sennheiser wireless sounds pretty good for voice. It is powered from the transmitter and is probably receiving around 3 volts or so.

I have a little Sony lav that is powered by a 3-volt powersupply or directly from the microphone power supplied from a Sony camera. It works OK but doesn't have the dynamic range of the ME2. For speech it is just fine.

Note that when I say speech, I mean the capture of dialog during an event like a wedding or an announcer's voice during a school graduation. What they say is important and one does have to be able to easily recognize their voice.

I do not mean the capture of a voice-over for a television commercial. In the case of a voice-over, I want everything I'm paying for in the voice and a lav just doesn't do it. so I use a large diaphram studio condenser microphone running on Phantom power.
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Old January 18th, 2004, 02:05 PM   #3
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Never beleive a salesman. Much of the time they know just enough to be dangerous and sell their product.

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Old January 18th, 2004, 02:34 PM   #4
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Re: bad advice from a pro re lav. Arrgh

<<<--1) I already used it with phantom power. did I ruin it? -->>>

Not necessarily. If the output of the AT is balanced, there should be blocking capacitors in the middle.

Why don't you try it, with the battery in (watch polarity!) and the mic input without phantom?

<<<--2) Is there ANYONE I can trust? -->>>

You salesmen? Or what?

<<<--3) The pro 7a is an electrect. Rose says externally-polarized condensers are better. Example of ext pol lav? -->>>

As far as I know there are no external polarity condenser lavaliers around now. There used to be some in the past that I got to know, made by Sennheiser and Beyer, but they were large and expensive.

Internally the voltage on most real condenser mics is reduced to a smaller voltage, so I don't know how many do see 48v actually. But the continuous polarity, whatever the voltage is their advantage over electrets.

<<<--4) dif b/t mics that use or do not use phantom power? -->>>

What's a b/t mic? A battery powered mic?

If the mic accepts both supplies, battery and phantom, they usually have a switch or some way to short circuit the battery place.

Be careful with cardioid lavaliers, as they are more tricky to use. You should only buy a cardioid lav if you already have an omni one. Cardioid lavs are more difficult to place, because things may get hard if the actor moves his head to talk, and more difficult to protect from physical noise (clothing, etc.).


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Old January 18th, 2004, 10:19 PM   #5
 
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The ATPro7A will simply ignore the phantom, so you haven't damaged it. Since many consoles can't even turn off the phantom, to my knowledge all microphones have protection, it's just that they won't work without a battery by refusing to pass the phantom power.
There are lots of good salespeople out there, you just hit a bad one. Music stores rarely have knowledgable prosound guys any more, but most professional audio stores, such as Leo's or Performance Audio, EAR, and the like....all have pro's that know what they're doing.
Regarding cardiod vs lavs, I have to loudly dispute this. Broadcast industry tradition has always held to omni mics vs cardiod. Traditions are meant to be challenged. We rarely use omnis, almost always cardiods. They CAN be tougher to use, but not if you know what you are doing. Check out the 3 Tenors work we did, it was all done on a live stage with cardiods, cardiods that had been cut into the bodies of pen-tops, since we couldn't show mics in the live show. Our work which has won Emmy's for sound, our work that has and ins currently showing at Sundance, also has all been recorded with cardiod lavs.
That's not to say that it's wrong to record w/omni's, but that it's a myth not easily accepted by audio folks. Further, you always have greater control with a directional mic vs an omni.
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Old January 19th, 2004, 06:09 AM   #6
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<<<-- Originally posted by Douglas Spotted Eagle :
Regarding cardiod vs lavs, I have to loudly dispute this. Broadcast industry tradition has always held to omni mics vs cardiod. Traditions are meant to be challenged. We rarely use omnis, almost always cardiods. They CAN be tougher to use, but not if you know what you are doing. Check out the 3 Tenors work we did, it was all done on a live stage with cardiods, cardiods that had been cut into the bodies of pen-tops, since we couldn't show mics in the live show. Our work which has won Emmy's for sound, our work that has and ins currently showing at Sundance, also has all been recorded with cardiod lavs. -->>>

Music shows are completely different from fiction or documentary projects. So what you say is quite likely valid in that world.

This is a fact that can be checked very easily: about 90% of all lavalier models made is omni, not cardioid. That is probably the opposite of "normal size" mics around, where cardioid types prevail. Why do you think that is? I would say because the market asks for that. It is not a tradition, but a need.

Please go and check what is written on Location Sound Corp catalog, on "Lavaliers - an overview":

"From a production standpoint, the use of directional lavaliers has not proved practical. Directional lavs have to be pointed precisely in the direction of the sound, and often times that is not just feasible when wiring actors with hidden mics... The most popular application for directional lavaliers has been PA, where feedback can be a problem for sensitive, omnidirectional lavaliers..."

Of course the explanation is longer and more in depth than this excerpt, but I think this states my point.

In musical performances there's another factor that helps you can get away with cardioid lavs: the singer knows the mic he is using, sings for it and always at it. That is certainly not the case with actors and most persons using a lav.

<<<-- That's not to say that it's wrong to record w/omni's, but that it's a myth not easily accepted by audio folks. Further, you always have greater control with a directional mic vs an omni. -->>>

Of course it's not wrong, it's outrageously RIGHT! By stating this you are saying, as used on a specific application, you risk making people think you are right, and you are not. You are only telling about your application on a musical project, which is a very special genre.

The people who read this forums are looking for help, and mostly unexperienced. So they will probably listen to what pros say and follow their advice. But as long as you don't explain the whole situation, like what you should on your musical projects or me on fiction and doc projects, they may think it's a generic advice. And their projects will suffer. Both in not achieving a clean sound as in making people insecure on other areas.

You can't have greater control with a directional mic if the actor/speaker does not talk into it, and that is essential to enjoy the benefits of a cardioid mic.

Cardioid lavs are very tough to use, as you well say, even for experienced people. Omnis are not, even for non-experienced people. That should be the only and clear thing stated here. All the rest just confuses the issue.


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Old January 19th, 2004, 10:47 AM   #7
 
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We rarely do music documentary or video projects. All of our work for broadcast is documentary in nature. If we do live music or multichannel input, it's always via a desk feeding a deck of either multitrack or DAT. The 3 Tenor's gig was no different, we fed the audio to a laptop/HD setup in the live situation and mixed it in post. Most of our Broadway show promo is interviews cut over live shots of a show with studio-recorded music as a bed, or our documentary work done as on-site work. Our "Azee' Choo'nii'gii'" project, showing now, was done in the field with completely inexperienced, never-been-on-camera talent, and it was all done with AT 899's, because we were on a run n' gun and knew we'd not have any control. The situation calls for whatever is used. Iprobably have a much larger mic box than the average videographer as well, but that's not an excuse for being uninformed or not practiced at the craft.
In summation, I'd much prefer to educate than to simply take the approach of "if you are beginner, get the easiest tool to use" as opposed to, "You're a beginner, get a good tool and learn how to use it."
Doesn't matter to me what Location Sound might or might not have to say on the matter, I'd submit that my own style and choice of tools has spoken loudly for itself over the past 25 years, and as a GENERAL rule, I always start with a directional mic. Control in post is very, very important to me.
Cardiods ARE tougher to use, but also better in most sitations IF used correctly.
Please don't assume that because of my strong background in music, I only do music projects. Most aren't. Most are either Broadway show promotionals, commercial spots, or indigenous documentaries. Plus some corporate training material.
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Old January 20th, 2004, 08:48 PM   #8
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Cardiods ARE tougher AND better

I started to read this thread because I am looking for a high quality lav, and I really have to agree with Douglas about cardiods vs. omni's.

I come from the radio world and there, people are always given the advice to use omni's because they are easier. I've always used Sennheiser, starting with Sennheiser 405's and now MKH 50. (or whatever length I need). Idon't see that it's really any different with Lav's.

The reality is that the time you save in mixing when you don't have to isolate the voice from some other errant sound is clearly worth the trouble to learn how to control mic placement, and frankly how to control interviewee's who like to turn their heads.

For the definite instruction on learning that control, I recommend DUNE - still the best.

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Old January 20th, 2004, 11:02 PM   #9
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<<<-- That should be the only and clear thing stated here. All the rest just confuses the issue.

Carlos -->>>

Ridiculous attitude, even if I agree with you. {on the usefulness of omnis cardioids, not the benefits of narrow-mindedness.}

Mostly, I've used omnis, because I usually feel like I can get them closer, and they seem less sensitive to clothing or hair noise. But It's good to hear the opinions of a long time pro, and I may give a cardioid lav a whirl.
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Old January 21st, 2004, 04:58 AM   #10
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<<<-- Originally posted by Martin Garrison :
Ridiculous attitude, even if I agree with you. {on the usefulness of omnis cardioids, not the benefits of narrow-mindedness.}-->>>

Don't think I don't agree with you on both issues, as I also think my claim is very narrow minded. And I wouldn't rely on it if the situation wasn't dramatic, or at least very serious.

In spite of Douglas seeming to know quite well what he is talking about, and of his years of experience being just a bit less than mine (which means we should know what we are talking about), the actual facts of omni vs directional lavs talk for themselves a bit louder than any of our voices. The relation between available omni to cardioid lav options is more than 10 to 1, which I think is a result of a market made of people picking omnis because they serve them better.

All choices involve compromise, as my colleague and I well know, so when people pick a tool over another is because the compromises are at a minimum for it. With experience and curiosity we create new challenges and demands, and sometimes we forget there are other people that are not aware of how important our baggage is in the new ideas we start to believe in. Which is not the case for most people. And I think it's where the danger is.

In my personal opinion, close up cardioids (in this case lavs) have a proximity effect I dislike. Omni lavs were different until the '80s on what they are now. Old omni lavs always sounded in close up, which is not natural when your image is not close. Modern omni lavs sound more natural, as if they were at mid distance, and mix better with boompoled mics, which usually provide a more natural sound and should be preferred.

<<<--Mostly, I've used omnis, because I usually feel like I can get them closer, and they seem less sensitive to clothing or hair noise. But It's good to hear the opinions of a long time pro, and I may give a cardioid lav a whirl. -->>>

That is the most important issue. Omni mikes are much less sensitive to clothing noise (when they are hidden) and to wind noise (when they are exposed). That maybe the most important reason for omni's preference, and justly so.

You should definitely try cardioid lavs and also get back here with your findings.


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Old January 21st, 2004, 05:26 AM   #11
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Re: Cardiods ARE tougher AND better

<<<-- Originally posted by Milt Lee : I started to read this thread because I am looking for a high quality lav, and I really have to agree with Douglas about cardiods vs. omni's.

I come from the radio world and there, people are always given the advice to use omni's because they are easier. I've always used Sennheiser, starting with Sennheiser 405's and now MKH 50. (or whatever length I need). Idon't see that it's really any different with Lav's. -->>>

Yes, it is different. You are confusing several issues here, if you allow me to say. General use omnis, particularly hand types, are more practical for three reasons: they tolerate high level sounds better, they are less sensitive to wind and they are less prone to handling noise.

Video/film watchers expect a certain sound from that hand mic, what I would call a "news sound". You can't use a MKH 405 or an MKH50 in your hand if you are not very careful. First of all you will have more proximity effect than on the omni, and the mechanical noise may be a serious problem.

Lavaliers are usually worn in the chest, which as I see it brings with it the proximity effect, which maybe nice on some occasions but not on all of them. On the same situation an omni may sound more natural, besides other advantages. The cardioid will isolate better from environment, but on most situations an omni being closer (also on the chest) is just enough for that as the sound source/noise relationship will improve.

When you are out of the lavalier world, cardioids are kings. You can be absolutely in control of all situations with them, which is not the case with lavs.

<<<-- The reality is that the time you save in mixing when you don't have to isolate the voice from some other errant sound is clearly worth the trouble to learn how to control mic placement, and frankly how to control interviewee's who like to turn their heads.-->>>

No doubt learning how to place your mic is the key, that is much before users moving their heads around. Things get even more difficult when they do. But noise problems, from rustling and wind, are more difficult to solve than any errant sound that may come by, and they are central on mic placement.

<<<-- For the definite instruction on learning that control, I recommend DUNE - still the best.-->>>

Please forgive my ignorance: what is DUNE?


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Old January 21st, 2004, 10:46 AM   #12
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Dune - the definitive instructions

IN THE BEGINNING...

Complex, brilliant and prophetic, Frank Herbert's award-winning Dune chronicles captured the imaginations of millions of readers worldwide and transformed their perception of what the future could be. By his death in 1986, Frank Herbert had completed six novels in the Dune series.

I took this from the website - http://www.dunenovels.com/

I first read DUNE back in the early 70's or perhaps late 60's. What I was amazed (besides the giant sand worms, and the water suits that people wore) was the ability that people developed to control other people by the words that they spoke, and the hand gestures, or movement of one's eyes. Such subtle movements could get a guard at a city to change his mind about shooting you, and allow you to pass a check point, unhindered.

Clearly this ability would be extremely valuable for working with interviewees or actors. Of course later on, people did develop these skills through the use of NLP - Neuro Linguistic Programming.

Milt Lee
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