Noise

S

scottfs

Well-known member
I did the sound for this short. It's along the American River, but I'm hearing a significant background noise. Equipment is ME66, Marantz PMD661, the usual cables, etc. I don't recall hearing this noise before. It seems to start at 1:14 in.

What is going on? I'm not happy. Is the recording set too high? I set it so it was just under the red lights.

https://www.youtube.com/watch?v=lsybzSzrMEg

Thanks for any help.
 
I hear what sounds like a highway and then at around 1:40 sounds like a fishing rod or something which was inorganic to the scene. Sound like environmental noise...
 
The quick shot of the girls running right before 1:14 sounds like the recording level was lower than the shot right after at 1:14. Sounds like the self noise of the equipment you used was more apparent because there was no running water in the background to hide it as well as the higher recording level you used.
 
What do you mean by "just under the red lights"? A technical term I've never heard.
If you mean just below clipping. PCM files may be ok but when encoded to AAC or another lossy format, clipping is likely.o l

I currently don't have speakers to listen to the clip.
 
I listened on headphones and I don't hear any added "noise" where you are talking about. The dialog has a very "boxy" sound, like you were too close maybe? Though that would be a very strange situation, probably something overloading a bit. Maybe a factor of being just "under the red lights".
Not a technical term but it does have a nice ring to it ;~)

Not that you asked for critique but I would also add a lot more sounds. You have a lot of actions where I would expect to hear something and don't.
 
Yes, just below clipping. I am not an audio engineer, just a guy learning on the job.

I suspect this is equipment noise. I've heard this sound before, but usually on low-quality recordings on the web, etc.

So, what is the best way to reduce this noise? Better mic? Better recorder?

BTW, thanks for the help!
 
scottfs said:
So, what is the best way to reduce this noise? Better mic? Better recorder?
Click to expand...
I hear a slight increase in what sounds like system noise around 1:14. But it is quite well covered by the ambient background noise which is why it doesn't stand out when most of us listen to it.

It isn't really possible to suggest any specific upgrade or change in technique because we know nothing about what gear you were using or how you used it (microphone placement, etc.)

The actual dialog sounds pretty well recorded, not too distant or off-axis, etc. So it seems quite possible that upgrading the microphone and/or the recorder (or mic preamp, etc. etc.) could improve the signal-to-noise ratio.

You said that you were watching the recording levels and keeping them pretty "hot". That is good. But were you ALSO monitoring/listening to what was being recorded? On a good set of closed headphones. Sony MDR-7506 is one of the favorites over on this side of the pond, and Sennheiser HD-280 over on the other side of the pond.
 
I have a Marantz pmd661, modified by Oade brothers. I use a Sennheiser ME66. Yes, I record with headphones. I do a sound check before each scene, and set levels so they are just under clipping at the highest point of recorded sound.

I'd like to have less 'electronic sound' to this.

What's the best, and most cost effective upgrade that would help? I've heard no complaints in my 20 or so films, but I'd like a cleaner sound.
 
scottfs said:
I have a Marantz pmd661, modified by Oade brothers. I use a Sennheiser ME66. Yes, I record with headphones. I do a sound check before each scene, and set levels so they are just under clipping at the highest point of recorded sound.

I'd like to have less 'electronic sound' to this.

What's the best, and most cost effective upgrade that would help? I've heard no complaints in my 20 or so films, but I'd like a cleaner sound.
Click to expand...

Have you considered other microphones? The ME66 has a very weak low frequency end and a somewhat exaggerated, brittle treble. In noisy environments this can be an advantage, sometimes, but it does tend to make voices sound thin and telephonic. (In my experience, it often works better with female voices than male.) An upgrade to a Sennheiser 416, Rode NTG-3 or Sanken CS-3e (my weapon of choice) will add some depth and richness to your recordings.

In a 24-bit digital recording environment, there's no reason to set levels to "just under clipping." What that really means is that you probably ARE clipping on brief transients that are too fast to show up on the meters. The dynamic range of modern recorders is pretty fantastic, and you can best take advantage of it by setting your levels lower, leaving plenty of headroom for the occasional unpredictable peak. While in fact almost anything that will wiggle the meters at all will probably be plenty clear, an average dialog level of -18 dbFS, with occasional visible peaks into the -12 range, is more than adequate to get a clean and low-noise recording without making the sound feel like it was pushed too hard.

- Greg
 
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Hardly anybody listens to movies, so lack of complaints really only means it wasn't really bad. Sound is really hard to talk about. So I'm not sure what you mean by "electronic sound". I know what I would mean but I suspect it's not the same.

What you may mean is the somewhat over modulated sound I mentioned. Or it could be a mic quality that you are noticing. Some folks don't like the sound of the ME66, which I hear described as overly bright or brittle. I haven't used one so?

I would try some things out to narrow down your issue. I would lower your levels as a first step. Try not to have your meters peak over -6dB and see if that helps. I suspect this is what I am hearing. You don't really want to push levels to just under clipping. For one thing depending on where the meters are reading you could be over modulating at the D/A converter if your digital levels go over -3dB.

If that doesn't fix things I would try a different microphone.

The PMD 661 is not spectacular from a preamp stand point. The upgrade should help but this recorder was designed for radio reporters and is a fair number of generations away from current equipment. If you can borrow a MixPre from someone for a test you could try that as a front end and see if the mic pres are the issue.

The point of all the above is that obviously nobody here has figured out what sounds "electronic" to you or recognizes what you are calling "noise". It doesn't mean you are wrong just that we are speaking different "languages". I have done sound work for a LONG time and one of my first tasks with a new director is working out the "language" so that when he says "it's too brow" or she says "it's kind of fuzzy" I know how to translate that to what I would call it.

Defining that language in a forum is very hard, and with out knowing what it is that you want to change it's near impossible to give any useful advice.

SOOOO if you run a few tests and figure out what is actually causing the problem then we can probably offer suggestions.

All mics sound different, some radically so. Mic pres all sound a bit different and often sound different at different levels at least a bit.

But I would start by lowering the record level. It's the cheapest and I think the "boxy" sound may be what you are hearing.
 
scottfs said:
I do a sound check before each scene, and set levels so they are just under clipping at the highest point of recorded sound.
Click to expand...

I'm going to chime in with the others and say that this is probably not a good workflow. Most people (define that how you will) tend to set their dialog peaks in the -12 dB range. There are good reasons to do that. One is to put less stress on the mic preamps, so you get less hiss in your recording. One is to put less stress on your AD converters. One is to make sure you don't clip anywhere in your electronics chain. One is to make sure you have enough head room for the unexpected from your actors. Also, set and use your limiters if you have them, typically at -2 or -3 dB. If things go right you'll never see your limiters activate, and that's a good thing. But if they do activate, you'll still "safe". That way it's nearly impossible for you to clip anything at all. You might want to give this "-12dB + limiters" workflow a try and see if it helps.

Another thing is that mic. Not a big favorite. And since you're sensititive to the noise, I'm not pointing you toward a MKH 416. I think you'd probably like a MKH 60, or an MKH 8060 better. You can find MKH 60s fairly easily on the used market these days. I like these for exteriors because of how they are made; the RF condensers don't create much in the way of static electric fields to attract dust/dirt to the diaphragm. The are also excellent high humidity mics (as you find near rivers, like in your sample clip).

I applaud your desire to improve your sound. While most viewers only notice when sound is bad, I'm one of those people who notice when it's good (and I comment on it, much to my wife's annoyance). I thank you for your quest to improve your dialog sound; it's not an entirely thankless task.
 
Thanks, all. I've only been doing production sound for about seven years, and I still have a lot to learn. I'm self-taught (there is very little professional film work in Sacramento). I've read as much as I can on sound, but only getting your hands dirty do you really learn.

I'll certainly try to lower the recording level. The Marantz has LED lights which are pretty fast. One problem I do run into is trying to do a sound check on actors. I don't think more than one or two have run through dialog the same way as when the camera is rolling. The sound check is basically them reading their lines.

I am certainly willing to upgrade my mic. I'm not wedded to any particular brand/model, the Sennheiser was recommended in reading material, which was probably years old.

Are used mics a good bet? It seems as though you are buying a pig in a poke.

Editing on these student films is all over the map, of course. I just want to give them the best sound I can. Then, it's up to them. No editor has ever asked me to sit in with them. I do give them notes, but have no idea if they read them.

Again, thanks. You guys are the greatest!
 
The fact that actors -- especially beginners -- are unpredictable is yet another reason to err on the side of caution and set your recording levels a little lower than you may be used to. My experience in analog recording goes way back, and believe me, it took some mental adjustment and trial-and-error to get used to seeing the levels only reaching halfway up the meter scale, or less, when I first got started with digital. But that's the way it is supposed to work now, and my recordings are better than ever before.

Of the two dozen or so microphones I own, about half were purchased used -- several through the classifieds right here on DVXuser. I've only been disappointed once, when a mic I bought on eBay looked quite a bit more worn and battle-scarred than the auction pictures led me to expect. But even then, there was nothing functionally wrong with it; the issue was purely cosmetic. All the others have been very satisfactory and many of them were pretty much indistinguishable from brand new. Since they're relatively simple, rugged and have a long useful life, I think microphones are one of the safer bets in the used equipment market.

Let us know what you wind up trying and how it works out.

- Greg
 
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I would consider most HH, shotgun and pencil type mics OK to purchase used and have gotten some great deals. However, I consider lavalieres as expendables, with a relatively short life span and frequently need to be retired/replaced. I would not buy a used lav unless it can be confirmed to be in very good condition.

Sound check?.. Maybe with a band, but not on a movie set. I've never expected one, nor would I even request one, unless in abnormal conditions or I wish to be fired or ridiculed. I just PFL the mics to confirm they're operating properly. YMMV though.
 
Well, I have found that it's really tough to tell how to set my levels unless I have the actors run through the dialog. I don't do this all the time, but when there is a lot of yelling, or whispering, I'm not that skilled to set my levels without hearing the dialog first. Most of the time, I don't do that, you're right. Chalk that up to my relative lack of experience. This is a part-time effort on my part, I only work maybe 30-40 hours per month.
 
Don't these folks rehearse? The rehearsal is generally when you can get an idea of dialog levels since they are closer to performance level. If you back of a bunch from your "just under the red lights" and get your levels down to where people are telling you you shouldn't have to worry so much about overs so even if the get a bunch louder you should still be OK.

Maybe now with digital everyone just rolls all the time? Must make editors happy ;~)
 
I think the levels are probably too hot on record and have probably got crushed in the edit. It's very easy in digital systems to forget that a hot signal on one channel and a hot signal on another (and perhaps more too) get summed internally, and then you have your master fader. Would I be right that yo had to drop the master fader to stop it going into the red? If you had to lower it, then you probably went over the top in the bussing, and this is where the hardness has crept in. You also have huge amounts of energy down the bottom, and this easily pushes the levels up. Too busy in the effects department - the location sounds, the sound of feet etc - all have appreciable energy. Pulling down the master doesn't mean it didn't go over level before it got that far.
 
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