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Old October 25th, 2020, 02:28 AM   #121
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Re: The fader on my field recorder does not have numbers, does anyone know?

You can move in progressively closer, you'll hear if the levels are getting beyond what the mic can handle before there's any damage.
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Old October 25th, 2020, 02:31 AM   #122
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Re: The fader on my field recorder does not have numbers, does anyone know?

Oh okay, but Greg Miller mentioned in his post before, that if you get too close, the mic can be damaged, no matter what the gain setting is though. He said even if there is no power running through the mic, it can be damaged. So therefore, how do you tell from gain what the mic can handle, if the mic can be damaged from loud sounds with the power turned off?

Quote:
Originally Posted by Greg Miller View Post
Ryan, the fact that you have asked this twice indicates that, sadly, you have absolutely no conception of how audio (mics, amps, sound waves, etc.) works. I say "sadly" because someone past high school who has so little understanding of the field would seem to be pursuing the wrong line of work and, I suspect, will always be frustrated.

Brian already answered this a few hours ago. Did you read his answer? If so, why are you asking this again?

This is so simple and should be so intuitive. The gain setting does not somehow send a secret message to the mic saying "don't be sensitive to large shock waves." If in fact a shock wave (from a firearm, as we're discussing here) is large enough to damage a mic, it wouldn't matter where the gain is set, or even whether the mic is plugged in. The damage is caused because the shock wave pushes the diaphragm further than it is designed to move. It's the same reason a human can have their hearing instantly damaged (or lost) because of excess pressure waves from gunshots.

As others have said, a scream is not the same as a gunshot. The former is some waveform that continues over a second or so, while changing in frequency, waveform, etc. A gunshot starts with a large sharp rise in air pressure, especially close to the muzzle. (Then there are various resonances, echoes from nearby objects, etc.) Additionally, a gunshot is much louder than a scream. All this info can easily be found on Google.

What would you do if you hadn't found a forum like this one? Would you then look for some books containing the appropriate knowledge? In all seriousness, do you have difficulty reading? (e.g. are you dyslexic?) If you can read normally, please go to the library or buy a few books about very basic audio, basic acoustics, etc. and read them. Unless you want to be very confused and needy for your entire life.
But let's say I go closer. Even at about 15 feet away, which I tried at one point, the fader was set to about 10% turned up and the gain was at about 2% turned up.

So even at these very low settings, I was still hitting -!2 decibles. So how do you get closer, to have a closer perspective, if it's going to be too loud if you do, since I am already hitting -12 decibels from about 15 feet away?
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Old October 25th, 2020, 03:11 AM   #123
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Re: The fader on my field recorder does not have numbers, does anyone know?

Ryan - we have explained and explained. The mic can be in it's box and damaged with exposure to a transient pressure wave - this is possible - but you've taken the advice out of context. We explained the physical action that could, not will, damage a mic - but we've also explained that people record gunshots every day, with their equipment close enough to sound VERY close, without damage.

Gain setting is totally different. Most people start with their gain set fully down. You then increase it to give a sensible reading on the meter. Some condensers are very sensitive, and have pads to give an extra 10 or 20dB of cut for louder sounds. If I put a mic on a kick drum, I will normally press the pad button because I know it's going too be hot. If the player is gentler, I might switch the pad out. Gains will be set all over the place - some turned up for quiet sources, others way down for louder ones - it doesn't matter, the idea is no distortion. The inverse square law. If your mic is one foot away, and too loud, move it to two feet and the sound drops to a quarter, not half of what it was. Move it to 4 feet and it's a 16th of the original. This is what really matters. You have been told quite rightly that too loud sound could damage - but you've taken that to mean too loud a sound will damage absolutely at ten feet, or six feet or whatever you have in your head. Sound simply doesn't work like this. If it did, the person who fired the gun you recorded would be deaf, wouldn't they?

If you really don't get this, now is the time to move out of sound. It's a subject area that needs good science, good ears and a solid foundation.

I tell you what. I have some very nice expensive mics and I'd be happy to put any of these a couple of feet from a gun and record it. I know, without trying that I'd switch on the pad on one of them, to stop audio distortion, NOT destruction - the pad won't stop that. The other would I am certain distort, but I would NOT be worrying about destroying them. The mechanics says that a bigger diaphragm would be more easily able to touch the two membranes or backplates together because the larger diameter makes this possible with less SPL. A smaller diaphragm is harder to deflect.

Would I put a condenser two inches from a gun muzzle? No
Would I put a condenser six inches from a gun muzzle? probably not
Would I put a condenser twelve inches from a gun muzzle? probably
Would I put a condenser two feet from a gun muzzle? yes

If the gun looked bigger (bearing in mind I know nothing about guns) then I'd increase the distances, but the reality would be I'd use a dynamic that didn't cost too much simply because there's more damage potential from the smoke and chemicals thrown out by weapons, not really the pressure wave.

You quoted Greg's excellent post without understanding a single word of it, didn't you?

You honed in on "the damage is caused" without even considering the rest of the sentence - as in gun = damage.

You know? Life is NOT risk free. In my life I have destroyed a number of microphones.

A coles lip mic, which I wrecked by attempting to unscrew near the ribbon without considering the magnetic field that grabbed the screwdriver, and squashed the ribbon.

A Shure bullet proof SM57, that isn't bullet proof under water when you drop it

An Audio Technica 815 shotgun that got turned into a banana when I stood on it.

The loudest thing was a radio pack and Sennheiser condenser attached to a drag racer - from the camera position it was deafening - no idea how loud it was cable tied to the spoiler, but it survived!
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Old October 25th, 2020, 04:45 AM   #124
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Re: The fader on my field recorder does not have numbers, does anyone know?

A dynamic mic is a handy piece of kit for recording effects and other things. You can put one in places that a shotgun mic won't fit.

It will also offer another option when recording voice overs etc.

https://en.wikipedia.org/wiki/Shure_SM57
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Old October 25th, 2020, 08:01 AM   #125
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Re: The fader on my field recorder does not have numbers, does anyone know?

Quote:
Originally Posted by Ryan Elder View Post
the shotgun mic, even if not damaged, would still sound too distorted because of the signal to noise ratio involving loud noises
Ryan, this indicates your complete lack of understanding of how audio works, and the appropriate terminology. If, at your age and your point in life, you still don't grasp the basics, after all the help and advice you've received here, I honestly think you should quit trying to be a sound man and pursue something else that is more appropriate for your skill set. Otherwise you are just banging your head (and ours) against a brick wall.
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Old October 25th, 2020, 08:09 AM   #126
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Re: The fader on my field recorder does not have numbers, does anyone know?

There have been loads of TV news sound recordists and one person camera crews who have recorded gun shots without the slightest problem over the years. While doing so, they haven't gone through all the double and treble thinking that Ryan is going through.
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Old October 25th, 2020, 08:11 AM   #127
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Re: The fader on my field recorder does not have numbers, does anyone know?

Quote:
Originally Posted by Paul R Johnson View Post
An Audio Technica 815 shotgun that got turned into a banana when I stood on it.
Paul: Could you then aim it to pick up sound from around corners? ;-)

That's a pretty painful list. I once put a jeweler's screwdriver through the diaphragm of a dynamic mic; like you I didn't consider the force of the magnet. Luckily it was a cheap mic. In my defense, I was then in my early teens.
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Old October 25th, 2020, 10:20 AM   #128
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Re: The fader on my field recorder does not have numbers, does anyone know?

Quote:
Originally Posted by Paul R Johnson View Post
Ryan - we have explained and explained. The mic can be in it's box and damaged with exposure to a transient pressure wave - this is possible - but you've taken the advice out of context. We explained the physical action that could, not will, damage a mic - but we've also explained that people record gunshots every day, with their equipment close enough to sound VERY close, without damage.

Gain setting is totally different. Most people start with their gain set fully down. You then increase it to give a sensible reading on the meter. Some condensers are very sensitive, and have pads to give an extra 10 or 20dB of cut for louder sounds. If I put a mic on a kick drum, I will normally press the pad button because I know it's going too be hot. If the player is gentler, I might switch the pad out. Gains will be set all over the place - some turned up for quiet sources, others way down for louder ones - it doesn't matter, the idea is no distortion. The inverse square law. If your mic is one foot away, and too loud, move it to two feet and the sound drops to a quarter, not half of what it was. Move it to 4 feet and it's a 16th of the original. This is what really matters. You have been told quite rightly that too loud sound could damage - but you've taken that to mean too loud a sound will damage absolutely at ten feet, or six feet or whatever you have in your head. Sound simply doesn't work like this. If it did, the person who fired the gun you recorded would be deaf, wouldn't they?

If you really don't get this, now is the time to move out of sound. It's a subject area that needs good science, good ears and a solid foundation.

I tell you what. I have some very nice expensive mics and I'd be happy to put any of these a couple of feet from a gun and record it. I know, without trying that I'd switch on the pad on one of them, to stop audio distortion, NOT destruction - the pad won't stop that. The other would I am certain distort, but I would NOT be worrying about destroying them. The mechanics says that a bigger diaphragm would be more easily able to touch the two membranes or backplates together because the larger diameter makes this possible with less SPL. A smaller diaphragm is harder to deflect.

Would I put a condenser two inches from a gun muzzle? No
Would I put a condenser six inches from a gun muzzle? probably not
Would I put a condenser twelve inches from a gun muzzle? probably
Would I put a condenser two feet from a gun muzzle? yes

If the gun looked bigger (bearing in mind I know nothing about guns) then I'd increase the distances, but the reality would be I'd use a dynamic that didn't cost too much simply because there's more damage potential from the smoke and chemicals thrown out by weapons, not really the pressure wave.

You quoted Greg's excellent post without understanding a single word of it, didn't you?

You honed in on "the damage is caused" without even considering the rest of the sentence - as in gun = damage.

You know? Life is NOT risk free. In my life I have destroyed a number of microphones.

A coles lip mic, which I wrecked by attempting to unscrew near the ribbon without considering the magnetic field that grabbed the screwdriver, and squashed the ribbon.

A Shure bullet proof SM57, that isn't bullet proof under water when you drop it

An Audio Technica 815 shotgun that got turned into a banana when I stood on it.

The loudest thing was a radio pack and Sennheiser condenser attached to a drag racer - from the camera position it was deafening - no idea how loud it was cable tied to the spoiler, but it survived!
Oh okay thanks. But how do you get the mic that close without the sound clipping though? I have the game turned up at 5% and the fader turned up at around 5%, or even less? I'm not sure how to get that close and get the levels down enough since I'm already at the bare bottom, and still getting close to clipping. My mic also does not have any pads which is the NTG-3 I was using.
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Old October 25th, 2020, 10:37 AM   #129
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Re: The fader on my field recorder does not have numbers, does anyone know?

Then you obtain an external pad. This is not rocket science.

Q. I need a pad, what do I do?

A. You get a pad.
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Old October 25th, 2020, 11:00 AM   #130
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Re: The fader on my field recorder does not have numbers, does anyone know?

Oh okay, but what I meant is they do not make a pad that is external for the NTG-3 either do they? At least not that I've been able to find.
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Old October 25th, 2020, 11:05 AM   #131
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Re: The fader on my field recorder does not have numbers, does anyone know?

Who is "they"?
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Old October 25th, 2020, 11:17 AM   #132
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Re: The fader on my field recorder does not have numbers, does anyone know?

"They" are those mysterious people who tell Ryan things that aren't always accurate.

Pads are also called audio attenuators, you can buy them as separate items, rather like you can buy adapters that allow T powered mics to use 48V phantom power.

There's the Audio-Technica AT8202 Adjustable In-line Attenuator, Hosa ATT-448 Input Attenuator, XLR3F to XLR3M, Whirlwind IMP-AD40 XLR Inline Barrel 40db Attenuator or Whirlwind IMP PAD Microphone Attenuator (-30dB) . I'm sure there are other makes.
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Old October 25th, 2020, 11:27 AM   #133
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Re: The fader on my field recorder does not have numbers, does anyone know?

How hard would it be to google "microphone pad" as a starting point?

For the sake of reference, the NTG3 specs say maximum level is 130dB SPL @ 1kHz. Typically that is the level to reach 1% distortion, but I'm not sure whether Rode uses the same reference.

For the record, I believe Whirlwind also makes a 20dB pad. Given that the NTG3 is such a hot mic to begin with, 40dB might be more appropriate for gunshots ... but that's just an educated guess on my part.
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Old October 25th, 2020, 11:35 AM   #134
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Re: The fader on my field recorder does not have numbers, does anyone know?

Oh okay, I googled pads for NTG-3 but all that came up so far, when I looked was wind protection devices.

I didn't know they were also called attenuators, thanks.

Well when you say 40 db may suit the NTG-3, do you mean a 40 db external attenuator, you buy for it?
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Old October 25th, 2020, 11:43 AM   #135
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Re: The fader on my field recorder does not have numbers, does anyone know?

Pads/attenuators work for any mic, so you just google a generic name, rather than for a particular model.

Why don't you google the examples given? You're expected to do some research for yourself.
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