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Old January 3rd, 2006, 11:43 PM   #16
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How come your film school doesn't have mixers to borrow?

Or a decent boom pole?

*Caveat: If students are using the equipment, it may not necessarily work.
You may be able to get the production to rent some gear for you. And if you're a student, you can sometimes get some gear rentals for a low price by striking a deal with rental houses. Sometimes they will give you a break to develop a relationship with their future clients.

Or at a few hundred bucks you can buy one. Although if you buy all your accessories, the costs really add up (headphone, windscreen later, mixer, cables). Ideally you might want to get a wireless too (or another microphone which you can plant somewhere).

Quote:
But if I get it at home depot, will people notice and think bad things?
I think they'll notice. If the cameraperson is listening on headphones and your do-it-yourself boom isn't any good, he'll be able to hear any rumble caused by handling noise.
If the boom is heavy, your arms will get real tired real quick. It helps if you bring some stuff to stand on... some people use appleboxes (they're just hollow wooden boxes). Milk crates are good because they can hold gear too.

The people will say bad things about crappy gear if the sound ain't so great.

2- It might help to experiment and see how you can get bad and good sound.

Common scenarios (roughly in order of magnitude):
If the mic isn't under 4ft to the talent, you're highly likely to get bad sound. Room echo/reverb and background noise will be very apparent. On wide shots, it's impossible to get the microphone close by boom. So you either shoot around it, or move the microphone closer via a wireless or wired connection (hide the mic somewhere on set).

The location background noise is really bad. Scout the location ahead of time, and try to anticipate what the sound will be like when you shoot (i.e. rush hour traffic).

Handling noise on the boom (use headphones and practice/listen).

Cheap shotguns indoors tends to sound bad.

Technical problems- levels too high/low. With the Varicam you should have a lot of range, but watch out for the times when actors are inconsistent in their levels (i.e. suddenly they start yelling because they're acting angry). And you probably want to monitor off the Varicam somehow... get a microphone extension cable (i.e. cablewholesale.com???) and run yourself a headphone feed that way.

With a mixer, setting levels is easier because you can set the camera to tone. That way the levels on your mixer corresponds to the levels on the camera.

Quote:
my professor in location sound at my film school
If he/she teaches at a film school, I think that says something. ;)

Now in defence of film school profs, some people really know their stuff and teach because they enjoy teaching. I wouldn't know in your case.
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Old January 3rd, 2006, 11:51 PM   #17
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Quote:
Originally Posted by Fred Retread
You're going to want one eventually for various gigs, but you can't run one and be the boom operator at the same time.

It would be a good idea to make sure you know everything you can about the shoot. What talent is going to be where and when? How far back is the cam going to be? Is it going to move around? Are there opportunities for repeated takes?

Your job is to keep the mic pointed at the talent as close as you can get it while keeping it out of the frame.
I'm one step ahead of you--I've arranged to go to the locations with the dp. Well, maybe not a full step--that's great advice for asking questions--the bloacking, the number of takes, the distance of the camera.

Basically I'm paranoid because while I've operated boom several times, the one time I've used this Oktava, there was a shocking amount of noise, and I'm really worried about it. So I guess the advice to practice is a pretty critical suggestion, too.

For some reason my teacher said I should have a windscreen even for indoors. As I said, I am skeptical of some of his claims. Many times he fails to really justify his dictates. Nevetheless, my point is that a ZEPPELIN would probably make the whole thing seem more professional. That is my thinking. It bothers me to spend money on something where the purpose isn't primarily functional. So I'm torn. But those Oktava's are really small. And don't have foam screens incidentally/

(i wonder how much those ZEPPELINS cost...)
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Old January 4th, 2006, 12:44 AM   #18
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Quote:
Originally Posted by Glenn Chan
How come your film school doesn't have mixers to borrow?

Or a decent boom pole?
im working on it. normally equipment goes out in relation to a specific assignment, and im working to bend that rule, slightly.


Quote:
Originally Posted by Glenn Chan
You may be able to get the production to rent some gear for you.
I'm scared to ask; it's a slightly long story how I came into this position, but it involved a comment I made at one time which was that I had sound equipment, when all I really have is an xlr cable, oktava and beachtek.



Quote:
Originally Posted by Glenn Chan
2- It might help to experiment and see how you can get bad and good sound.

Common scenarios (roughly in order of magnitude):
If the mic isn't under 4ft to the talent, you're highly likely to get bad sound. Room echo/reverb and background noise will be very apparent. On wide shots, it's impossible to get the microphone close by boom. So you either shoot around it, or move the microphone closer via a wireless or wired connection (hide the mic somewhere on set).
...

Technical problems- levels too high/low. With the Varicam you should have a lot of range, but watch out for the times when actors are inconsistent in their levels (i.e. suddenly they start yelling because they're acting angry). And you probably want to monitor off the Varicam somehow... get a microphone extension cable (i.e. cablewholesale.com???) and run yourself a headphone feed that way.

With a mixer, setting levels is easier because you can set the camera to tone. That way the levels on your mixer corresponds to the levels on the camera.
Right. Thanks. I am really coming to that, that I need to do little experiments in my crash course here. The main thing is that I have had this one experience where I was responsible for sound on my own project, and then suffered the consequences when I came to edit it. I haven't had any experience except for that one, uncorrected negative experience (that is to say, where I did the production and post production sound; I have operated boom several times before, but I never had to deal with it in post, and those were not my projects). So I need to have some positive experiences. Thanks for getting me there.

Now, the main problem (at least so far as I can tell) in my negative experience is that the mic was placed at different distances from the actors. It was within four feet, but sometimes it was two feet and sometimes it was four and sometimes maybe five or something. This seemed to have a disastrous effect. From take to take, the noise levels and timbre varied greatly.

I have the beachtek dxa-8, which has limiters. wouldnt that be a safer thing to use than riding the pots? i tried to ask the teacher today what limiters sounded like but he refused to answer, saying it was subjective and i would have to decide myself (im not quite sure but they seem to sound artificial. i think they kicked in on this negative experience project i keep mentioning but im not quite sure). here is a link to the audio in question: http://solvemycase.com/case/oktava-nitemare.mp3 (there is music on the track which obscures the noise, but as you'll hear the noise is quite apparent. there are audio transitions applied from within FCP, but apart from that and some levels adjustment, no post audio work was done)

do you happen to know if the varicam has headphone outs, and if so what kind? it occurred to me that it might be more accurate to listen to the headphones out of the camera than out of a mixer (if there ends up being a mixer) but im not sure.

im still trying to figure out the setting levels tone thing. ive seen it demonstrated a couple of times but i dont get it.
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Old January 4th, 2006, 04:49 AM   #19
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Quote:
Originally Posted by Fischer Spooner
it's a slightly long story how I came into this position, but it involved a comment I made at one time which was that I had sound equipment, when all I really have is an xlr cable, oktava and beachtek.
Yikes! That's not a good situation. I think you've dug yourself in a bit of a hole here and are now trying to dig yourself out by asking a few people on the internet. I'm not sure if you'll be able to pull it off but there has been a lot of good advice given so hopefully things will turn out alright.

I personally can't give a whole lot of advice on this topic because I'm just starting to do non-stick mic audio on my shoots. Best of luck!
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Old January 4th, 2006, 07:27 AM   #20
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Quote:
Originally Posted by Fischer Spooner
10-4, Fred. I had a strong suspicion that there would be some who might say that a mixer wouldn't be necessary such a situation.

One thing that continues to bother me is it seems to me that it would be better to do that roll off at the point of committing something to tape, rather than later in post. Maybe I'm wrong. The question is, is EQ'ing better done in production or in post?

I guess I really just want to know what mixers are critical for, and what you give up when you don't use them.
True, equalizing and other sonic manipulation is best done in post but a high-pass filter on the mic itself to cut the lowest frequencies in order to minimize wind and handling noise or to reduce the "proximity effect" when close mic'ing is a good option to have. Those low rumbles and thumps can contribute to overload and clipping during the recording process yet contribute nothing to the desired signal. If you can get rid of those noises at the mic your recording will be cleaner.
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Old January 4th, 2006, 07:56 AM   #21
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Quote:
Originally Posted by Fischer Spooner
...

For some reason my teacher said I should have a windscreen even for indoors. As I said, I am skeptical of some of his claims. Many times he fails to really justify his dictates. Nevetheless, my point is that a ZEPPELIN would probably make the whole thing seem more professional. That is my thinking. It bothers me to spend money on something where the purpose isn't primarily functional. So I'm torn. But those Oktava's are really small. And don't have foam screens incidentally/

(i wonder how much those ZEPPELINS cost...)
The reason to use at least a foam windscreen even indoors is you're going to be moving the mic around during the shot as you follow the action. Wind noise is caused by air flowing past the mic diaphram and of course it doesn't matter if it's the air moving over a stationary mic or the mic moving through stationary air. Even if the mic is still, if the talent is speaking close to it their exhalation is air movement and if it impacts the mic you'll have noise.

Quote:
do you happen to know if the varicam has headphone outs, and if so what kind? it occurred to me that it might be more accurate to listen to the headphones out of the camera than out of a mixer (if there ends up being a mixer) but im not sure.

im still trying to figure out the setting levels tone thing. ive seen it demonstrated a couple of times but i dont get it.
It's best if you have the option for both. A "snake" or breakway cable between a boom operator/mixer and the camera will have a bundle of several cables. One pair is the signal going to the camera's inputs from the mixer. Another cable would be the headphone return from the phones output on the camera to a tape return input on the mixer. Some pro quality preamps and mixers like the Sound Devices MixPre have a headphone monitor switch where the boom operator can listen in his headphones either to the signal that the mixer is sending to the camera or to the return coming back from the camera.

Setting levels to tone simply means you have a standard reference tone in the mixer that when switched on goes through the mixer output stages and meters and on to the camera. If there's not one built-in to the mixer, you can get plug-on versions that plug into a mic input. During setup you turn on the tone and you'll see its levels on the meters on the mixer. The mixer gain control sets its output level and you adjust it so the tone reads 0db on the mixer's meter. Leaving the mixer alone you look at the camera meters and adjust the camera input level controls so the tone reads the camera's optimal recording level - for miniDV that's usually about -12 to -6db but check the camera documentation - I know nothing about varicams. Turn off the tone at the mixer. Now when the mixer operator see the meters bouncing at 0db during the shoot, you'll know the level in the camera is also on the money. The mixer operator uses the mic faders and the master gain to insure he's sending 0db levels down the line to the camera.
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Last edited by Steve House; January 4th, 2006 at 08:38 AM.
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Old January 4th, 2006, 02:06 PM   #22
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Quote:
I have the beachtek dxa-8, which has limiters. wouldnt that be a safer thing to use than riding the pots? i tried to ask the teacher today what limiters sounded like but he refused to answer, saying it was subjective and i would have to decide myself (im not quite sure but they seem to sound artificial. i think they kicked in on this negative experience project i keep mentioning but im not quite sure). here is a link to the audio in question: http://solvemycase.com/case/oktava-nitemare.mp3 (there is music on the track which obscures the noise, but as you'll hear the noise is quite apparent. there are audio transitions applied from within FCP, but apart from that and some levels adjustment, no post audio work was done)
The limiters are there just as safety. Instead of getting clipping, you get distortion instead. A little limiting isn't really noticeable, but when you get a lot of it then it definitely is noticeable. It's better-sounding than clipping at least.

Probably the best thing you can do is to just hook your beachtek up into a camcorder or your computer. Record at various levels, especially when you start hitting the limiter. And just play back the audio on your computer to see what limiting sounds like.

About :25 to :28 in your clip sounds like the limiter kicking in.

2- I'm not 100% sure, but I don't think the Varicam has limiters. I don't think it has a miniplug input either, so I'm not sure if it'd make sense to use the Beachtek.

For "professional" formats, tone should usually be set at -20dBFS (dBFS refers to decibels in the digital realm, not analog; 0dBFS is always the point of digital clipping). That gives you 20dB of headroom before clipping.
Consumer formats use -12dBFS for tone, which gives less headroom. This is generally because it's assumed that consumer equipment has higher noise. So less headroom means better S/N ratio.

Anyways, you can put your levels wherever you want. If you forsee actors yelling, then maybe you want their normal dialogue to peak at -30dBFS. So if they yell, it should be hard for them to clip the inputs. If their levels will be pretty even, then you can just set their levels to peak at -20dBFS. On the Varicam, the side of the camera will have audio meters.

You can also set the second channel to record the on-camera mic, or another XLR input. If you have one mic, you can record it onto both channels. On the second channel, lower the recording level. In case the first channel clips, you'll have the second as a backup. I'm not sure, but the Varicam may be able to do this without a mixer- check the manual (it's hidden in the Panasonic site under support).
If you do things this way, you could have dialogue peak at -20dBFS on the first channel and -40dBFS on the second channel. (These numbers are pretty arbitrary. They can be whatever you want.)

3- I have never heard wind noise when moving a mic around indoors when booming. You could test by swinging your Oktava around and see if it picks up wind noise. And blow wind into it as a control. I really don't think you'd need a windscreen.

4- Tone generator: You could record tone onto a miniDV camera and use it to generate tone.

5- The Varicam I think uses the same headphone output as the headphone outputs on a computer- the 3.5mm/eighth-inch/mini-plug connectors. You can double check with the manual.

Monitoring off the camera's headphone out is a good idea because things can screw up from mixer to camera.
Monitoring off the mixer is useful if you have more than one input, since some mixers can solo an input so the mixer can listen for problems. The better mixers have a return feed so you can easily switch between camera and mixer sound.

6- Your clip:
Getting the mic closer would've helped. You should really try to be within 1-2 feet to get good sound.
To get the mic into the shot as close as you can, dip the boom into the shot. Then back off until the camera operator tells you the boom in not in the shot. Be sure to make sure the camera viewfinder doesn't crop off the overscan area. Various ways to do this: use an external monitor with underscan, or knowing the camera and reading its manual will do it.

The location also makes a difference. Sometimes some stuff will happen that's not in your control.

There are things you can do in post that will make the noise less objectionable (laying room tone underneath, noise reduction plug-ins, hiding the noise with other music). However, it is much better to capture sound right in the first place. Fixing sound in post takes much longer to do than in production.
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Old January 4th, 2006, 02:24 PM   #23
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Quote:
Originally Posted by Glenn Chan
...

3- I have never heard wind noise when moving a mic around indoors when booming. You could test by swinging your Oktava around and see if it picks up wind noise. And blow wind into it as a control. I really don't think you'd need a windscreen...
It can happen but the little foam thingys are usually enough to control it.
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Old January 4th, 2006, 09:05 PM   #24
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TONE IS FOR MATCHING UP THE METERS (on the camera and the mixer), RIGHT?

Quote:
Originally Posted by Steve House
During setup you turn on the tone and you'll see its levels on the meters on the mixer. The mixer gain control sets its output level and you adjust it so the tone reads 0db on the mixer's meter. Leaving the mixer alone you look at the camera meters and adjust the camera input level controls so the tone reads the camera's optimal recording level - for miniDV that's usually about -12 to -6db but check the camera documentation - I know nothing about varicams. Turn off the tone at the mixer. Now when the mixer operator see the meters bouncing at 0db during the shoot, you'll know the level in the camera is also on the money. The mixer operator uses the mic faders and the master gain to insure he's sending 0db levels down the line to the camera.
Gawd; thanks, I finally get it now.
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Old January 4th, 2006, 09:38 PM   #25
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Originally Posted by Jay Massengill
Sound quality drops with each drop in price.
In battery-powered mini desktop mixers there is the Behringer MXB-1002 and someone else has mentioned the UBB-1002. I don't think the Oktava will like running on less than 48-volt phantom though. The MXB-1002 doesn't make full 48-volt power when running on batteries.
Oyyyyyyyyy.

Teacher sez a low quality mixer is for sure better than no mixer at all both for riding the pots as well as EQ/roll-off. The 1002 seemed promising in the sense that it apparently allows some measure of professional mixing at a low entry price, as well as opening up to 3 channels for lavaliers in addition to a boom, for example. I was going to take the plunge ($100 is a HUUUUUGE amount to me now).

The idea that it doesn't provide a full 48 volts of phantom power seems really alarming.

What does that really imply? First of all, does it mean that there is only a problem when outdoors/on batteries?

Quote:
Originally Posted by Glenn Chan
For "professional" formats, tone should usually be set at -20dBFS (dBFS refers to decibels in the digital realm, not analog; 0dBFS is always the point of digital clipping). That gives you 20dB of headroom before clipping.
Consumer formats use -12dBFS for tone, which gives less headroom. This is generally because it's assumed that consumer equipment has higher noise. So less headroom means better S/N ratio.

Anyways, you can put your levels wherever you want. If you forsee actors yelling, then maybe you want their normal dialogue to peak at -30dBFS. So if they yell, it should be hard for them to clip the inputs. If their levels will be pretty even, then you can just set their levels to peak at -20dBFS. On the Varicam, the side of the camera will have audio meters.

You can also set the second channel to record the on-camera mic, or another XLR input. If you have one mic, you can record it onto both channels. On the second channel, lower the recording level. In case the first channel clips, you'll have the second as a backup. I'm not sure, but the Varicam may be able to do this without a mixer- check the manual (it's hidden in the Panasonic site under support).
If you do things this way, you could have dialogue peak at -20dBFS on the first channel and -40dBFS on the second channel. (These numbers are pretty arbitrary. They can be whatever you want.)
Wow! great idea! I'd never heard that. That seems like the thing to do *everytime* you have one boom and two channels.

I don't know to what extent this is standard practice but it's the first time I've heard it, and it seems to me that it is a very useful practice (far more useful than recording two tracks at the same level, for obvious reasons--I can't imagine what good that really does), and it mystifies me somewhat that I have never heard that anywhere before. It makes me speculate that maybe it is *not* quite standard practice, at least in some circles.

The numbers which preceded this advice (-20dBFS, -30dBFS) were a bit over my head. I still get intimidated when I start hearing dBs getting thrown around. I'll have to revisit them.
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Old January 4th, 2006, 09:44 PM   #26
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Fischer,

You dont say where you're located, you might try craigslist for possible mixer sales. Lots of musicians and garage studios looking to upgrade, you could pick something up local for cheap.

Yes, sending tone to camera and matching levels is standard operating procedure.
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Old January 4th, 2006, 09:45 PM   #27
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Are you sure the 1002 doesn't have phantom? I found, by accident, that my sennheiser ME66 mic was magically on all the time when plugged into the mixer, whether the battery switch was on or not.
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Old January 4th, 2006, 09:47 PM   #28
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JOsh,

I believe it's not a full 48v phantom, but something like 9-12v or such.
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Old January 4th, 2006, 09:53 PM   #29
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My sense at this point, all things considered, is that I'll get the best results by getting a Behringer, plugging it into an extension cord, and recruiting a fellow student to operate boom.

Getting someone to operate boom competently shouldn't be too much of a problem. But now I'm worried about the little Behringer for field use. I've never used a mixer for this before (I've done audio engineering coursework, and mixed plenty of audio for my band, but I've never mixed a boomed microphone).

I'll do some research.
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Old January 4th, 2006, 09:57 PM   #30
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Quote:
Originally Posted by Richard Alvarez
Yes, sending tone to camera and matching levels is standard operating procedure.
That's not what I was talking about, silly! I was talking about recording two tracks from one input at different levels.

See, there's something inherently nerve-wracking to me about riding the pots all the time. It's like when you're operating camera and you're always adjusting the frame, and then you go to edit it, and you're like "who fed the operator crack?"
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