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Old October 24th, 2020, 01:36 AM   #106
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Re: The fader on my field recorder does not have numbers, does anyone know?

Why are we back to this?

On paper, loud sound can damage a thin mic capsule diaphragm, but I have never found any of my microphones, or my physical colleagues microphones damaged this way. I would suggest the chances of s loud sound making you drop the mic would be far more risky.

Forget this ryan, there's every chance it will distort but even that will be a transient you can edit. Move on and smile a bit. This one is not worth brain power.
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Old October 24th, 2020, 01:42 AM   #107
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Re: The fader on my field recorder does not have numbers, does anyone know?

The mic will be damaged by the sound if it's far too loud. The same thing can happen to your ear drums, if it comes in the form of a shock wave from an explosion, it can even kill you. However, it's unlikely in this case. since you're not recording right beside the muzzle of an artillery piece, as Paul says distortion on the recording is the more likely outcome.

This is a physical effect, which has nothing to do with the gain levels used on your recorder..
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Old October 24th, 2020, 06:09 AM   #108
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Re: The fader on my field recorder does not have numbers, does anyone know?

Think of what can actually happen. You have a backplate and then a thin film of mylar or similar. In a typical electret, the film has a permanent charge on it, that lasts for years and years. If the sound pressure level is high enough to make the flexible element make contact with the rear plate, the charge dissipates instantly, and the capsule is dead. A near excursion might over stretch it, but a short is the likely killer, and to do that it needs to be VERY, VERY loud, and I doubt even a moderately close gunshot is enough. Your ear drums are likely to get damaged more than a microphone, being fair.
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Old October 24th, 2020, 07:40 AM   #109
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Re: The fader on my field recorder does not have numbers, does anyone know?

As mentioned earlier, dynamic microphones are more resistant to damage from loud transients than condenser mics.
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Old October 24th, 2020, 07:53 AM   #110
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Re: The fader on my field recorder does not have numbers, does anyone know?

The trouble is, we've all been told that exposure to loud sounds destroys condensers, and the physics matches completely, but what none of us have, is a figure for spl@distance=destruction. We sometimes have max SPL - but is this for the point of distortion reaching maximum, or output reaching saturation, or what......?
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Old October 24th, 2020, 09:09 AM   #111
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Re: The fader on my field recorder does not have numbers, does anyone know?

Quote:
Originally Posted by Greg Smith View Post
As mentioned earlier, dynamic microphones are more resistant to damage from loud transients than condenser mics.
Oh okay well for the one short film I recorded audio on, I recorded an actor screaming, in the same scene as dialogue and it was all using the same mic. I turned down the gain a lot, but the scream didn't seem to destroy the mic and the mic still worked fine.

So if a mic can take an extremely loud scream, could it take a gun shot as long as the gain was turned down extremely low, and I stood back about 10-20 feet as mentioned before?

On microbudget productions, if there is only one mic in the budget, do they just use that to record everything, but take precautions to prevent damage?
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Old October 24th, 2020, 09:37 AM   #112
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Re: The fader on my field recorder does not have numbers, does anyone know?

A gun is usually louder than a scream, but shorter in duration. Indoors it will have even more impact.

This is going over old ground, Haven't you read the previous 7 pages, where the technique of recording gun shots was explained? Can't you work out a progressive method of moving in closer with each shot, so everything is recorded in a methodical and safe way? .
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Old October 24th, 2020, 10:10 AM   #113
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Re: The fader on my field recorder does not have numbers, does anyone know?

Ryan - put a sound app on your phone and get somebody to fire a gun (I hear this is absurdly easy throughout the Americas). These apps will tell you how loud it was If you can get a reading.

Have you thought about every recorded gunshot you have ever heard. None of those - absolutely NONE killed the microphone. You are dreaming up dangers that are extremely tiny. If the shooter doesn't go instantly deaf, then the mic will be fine. The damage comes from putting the microphone in VERY VERY close to the muzzle where the pressure is greatest. You point your mic, you watch the display. If it goes off the top, the gain was too high. If you have a zoom or similar it will have pads and one combination of pad and gain adjustment will work perfectly well. I'd suggest that until you are within 3 feet of the muzzle your worst problem will simply be distortion, not damage. The inverse square law means the volume drops very quickly as you move away. Watch the American crazy gun videos and see people with cheap cameras recording shooting at ranges - they are not being destroyed.
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Old October 24th, 2020, 11:36 AM   #114
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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
So if a mic can take an extremely loud scream, could it take a gun shot as long as the gain was turned down extremely low,
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.
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Old October 24th, 2020, 01:25 PM   #115
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Re: The fader on my field recorder does not have numbers, does anyone know?

Buy this book:
The Sound Reinforcement Handbook by Gary Davis, Ralph Jones, Gary Davis

It's full of useful information AND the physics behind it - and it's from Yamaha, so a manufacturer of long standing. My understanding is they commissioned the book to correct misunderstandings in the live sound world where mistakes can be uncorrectable - there being no take 2!
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Old October 24th, 2020, 04:29 PM   #116
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Re: The fader on my field recorder does not have numbers, does anyone know?

I've read the Yamaha book. It's everything you want to know about PA systems, preamps, mic types, gain staging, etc.

I learned a lot of the basics from a hardback about radio broadcasting, which was published by CBS. That was MANY moons ago. I have since tried to find the book, but without success; I'm sure it's long out of publication. Also the Audio Cyclopedia was a great resource, but is much too deep for beginner-level reading.

I think it might be helpful if other folks would make suggestions for Ryan's reading list.

Last edited by Greg Miller; October 24th, 2020 at 05:57 PM.
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Old October 24th, 2020, 06:46 PM   #117
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Re: The fader on my field recorder does not have numbers, does anyone know?

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.
Oh okay I see thanks, sorry for my misunderstanding of it. Well I managed to get out today, and record some gunshots. I couldn't set the fader at unity like normal, because it's way too loud for a gun shot if you try to turn it up to unity. I turned the fader up to 15% and the gain up to about 5% or even lower for some of the guns.

At these settings the levels were around -24 decibles, some shots reached -12.

However, I am not happy with because they sound like any other online. They sound too far away. I stood about 10-20 feet away like I was advised to on here, but that changes the perspective though. Or here are some samples, what do you think of them?


Last edited by Ryan Elder; October 24th, 2020 at 11:36 PM.
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Old October 25th, 2020, 01:54 AM   #118
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Re: The fader on my field recorder does not have numbers, does anyone know?

Why did you think unity was where the gain would go? They sound exaltly like what they were distant gun shots, so why didn't you carry on the experiment and shoot a few at closer distances? His would let you be used to how the gains/pads work. You are just doing what you did in your old shotgun mic tests. Too far away. If you personally find the bangs too loud so hearing protection would be sensible, that's the closest I'd want to go. The only weapon I have ever held and fired was a shotgun, but I'd have risked any of my mics where my ears were.

If you want audio perspective to sound real for the context, then use a video camera and then you can see if it sounds right and the images match the sound.

You've heard mics can be destroyed, and have over-reacted as usual. Listen to sound effect library gunshots. If they recorded them close, so can you. Tell you what, look up the spl for the level a snare or kick drum creates with mics just an inch or too away. Plenty of mics work for these loud sources, and one of them is pretty cheap and bomb proof. If you are worried this much, borrow an SM57 or D112 and put them very close. The won't even notice!

However, on recording forums you often find beginners complaining their kick is distorted. People explain the pads and gain settings, like here, but NEVER have I found somebody who destroyed their condenser mic, they just got a poor sound.

If you are going to experiment, do it properly
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Old October 25th, 2020, 01:58 AM   #119
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Re: The fader on my field recorder does not have numbers, does anyone know?

There's a point when you can't get any closer because you can't adjust the levels any further. I would take it up to - 4, which I know works with the drums on our local loyalist bands. Setting that level with a gun, will be a bit more fiddly, because there's no steady beat. You can use pads or attenuators on the mic, which allow you to get closer,

Analogue tape recordings can sound rather good when driven over the mox levels on the meter for some sounds, but you can't do that with digital.

I'm not sure why you should think your gun shots would sound much different to those recorded by other people. If you want different you need to experiment more, which what the guys who create the major sound effect libraries do.

Also, bear in mind, the gun effects used in feature films are mostly created in post by the sound people by combining various gun sounds. They may have their own favoured cocktails in their personal sound effects library.
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Old October 25th, 2020, 02:21 AM   #120
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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
Why did you think unity was where the gain would go? They sound exaltly like what they were distant gun shots, so why didn't you carry on the experiment and shoot a few at closer distances? His would let you be used to how the gains/pads work. You are just doing what you did in your old shotgun mic tests. Too far away. If you personally find the bangs too loud so hearing protection would be sensible, that's the closest I'd want to go. The only weapon I have ever held and fired was a shotgun, but I'd have risked any of my mics where my ears were.

If you want audio perspective to sound real for the context, then use a video camera and then you can see if it sounds right and the images match the sound.

You've heard mics can be destroyed, and have over-reacted as usual. Listen to sound effect library gunshots. If they recorded them close, so can you. Tell you what, look up the spl for the level a snare or kick drum creates with mics just an inch or too away. Plenty of mics work for these loud sources, and one of them is pretty cheap and bomb proof. If you are worried this much, borrow an SM57 or D112 and put them very close. The won't even notice!

However, on recording forums you often find beginners complaining their kick is distorted. People explain the pads and gain settings, like here, but NEVER have I found somebody who destroyed their condenser mic, they just got a poor sound.

If you are going to experiment, do it properly
Oh okay, it was just pointed out on here before that getting real close could damage the mic, so was weary of doing that therefore. It was also pointed out before that the shotgun mic, even if not damaged, would still sound too distorted because of the signal to noise ratio involving loud noises. So I was trying to avoid distortion as well. But I was more so afraid of the mic getting damaged possibly from being too close, as pointed out.

But when you say 'why did I think unity is where the gain would go', I said that I started out with the fader at unity, not the gain. It was said before on here, to start out with the fader at unity when setting the levels, so that's what I was doing.
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