Audio Settings. Simply explained for beginners.

versioncity1

versioncity1

Active member
Can someone explain setting up the dvx100ae for sound.

1. For on board mic
2. shotgun via Input 1 or 2.
3. Internal settings via menu.

Please could you mention:
a: input1 & 2 switch on front of camera (line/mic)
b: CH1 & 2 switch behind LCD. - this is what I'm mainly unsure of, how they should be set and the combination of the two.

Many thanks
 
The line/mic switches should be set to "mic" when you are pluging a microphone into the XLR connectors correspondingly labeled input1 & input 2 just around the corner from those switches. If you are only plugging in one mic you must have it's corresponding front switch in the mic position.

You only use "line" if you are taking the output from: a mic pre-amp (a separate box to amplify the mic signal to a higher level called "line), or from an audio mixer than can blend more than one sound source together in one output signal, or from a CD or tape player, etc. "Line" level refers to the specific electrical level range or "strength" of the signal. MIC levels are always MUCH lower than LINE.

The channel select switches, labeled "CH1 select" & "CH2 select, behind the LCD, is like a traffic cop that directs which signal to take and put onto which channel on tape. There are only 2 audio channels on tape, 1 & 2.

The seletor switch marked "CH1 Select" can take it's input signal from:

1) The camera mounted stereo mic that comes with the camera. Stereo is 2 channels, left and right. The first position, int (L), is to select the left part of the onboard stereo mic and put it's ouput (what it's hearing) onto channel one on the tape.

2) The next switch position takes the signal from the "input 1" XLR audio connector mentioned previously and put it's signal to channel 1 on the tape.

3) The final switch position for the "CH1 Select" switch takes the signal from whatever is plugged into the "input 2" XLR and puts it on to channel 1 of the tape.

THe CH2 select switch only has 2 positions it can take signal from: the right side of the onboard stereo mic or what ever is plugged into the "input 2" XLR.

In the Audio world, when working with 2 inputs, it is common to think of the "left" signal as channel 1 and the right signal as channel 2. It is by no means a rule however. Remember that regardless of which tape channel you record to, you can later change it's position in the stereo field by "Panning" it in whatever NLE you are using.

If you only have one mic plugged into input 1 then you need to select "input 1" on the CH1 switch, IF you want it to go to channel one on the tape.

If you want to select some ambient sound that you can later adjust in post you could also select "int (R)" on the "CH 2 Select" switch and record the ambient sound to channel 2. You don't HAVE to do this, it just allows easier adjustment of ambient sound level (volume) compared to whatever you are recording on the other channel to balance YOU want when you are editing.

If, on the other hand, you do not want any thing on channel 2 from the on board stereo mic, you must select "input 2" on the CH2 select switch, assuming you have nothing plugged into input 2 OR you turn down the level control marked CH2.

Hope that helps.

Ken
 
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I'd add one little tip/emhpasis: whenever using a single mic into Ch. 1, always send the Internal Mic to Ch. 2... it will serve as either ambience or backup... and sometimes in something like an interview situation it makes it easier to hear the directors questions. The second channel has many backup/ancilary uses, so rather than record nothing to it, record something to it... you never know and it's very little additional effort.
 
Yes!

You can delete or modify (change volume, pan, add effects, etc) or mute any audio track in post. AND if you have dialog on one track and ambient on the other, you can balance the volumes of both to suite your taste.

I believe most people find that just dialog with no ambient sounds sterile and unnatural, however that does not mean you are stuck with having to use "bad" ambient with unwanted noises, etc. Most NLE's allow you to cut the unwanted sounds out and or add effects like reverb to simulate room sizes. You may also find that the ambient that comes through on the dialog mic, is just the right amount and needs no adjustment. Once again, as David points out, it nevers hurts to have a backup track, you can always delete or mute it.

You can also "pan" the channels (in the NLE ) to anywhere in the stereo field so you can match the location of the sound source position on video with the audio dialog, etc. It would be terrible to see a person talking on the left side of the screen but hear their voice as if it were coming from the right.

Ken
 
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Another tip

When doing a sound check; ya know

Test 1, 2 Test !

You are cheking for peaking (Audio Levels). Keep the bar under the RED at the loudest point CHECK ! CHECK 1, 2 CHECK !
 
Keep the bar under the RED at the loudest point CHECK ! CHECK 1, 2 CHECK !
Click to expand...
I believe with DVX100 you can(and should) go well above RED, at least 3-4 more RED point... Otherwise levels will be so low...
 
I've never had this problem following what I said; I have found that that is when I experienced that nasty SQUELCHY satan sound

Then again, I am not a self professed audio guru.
 
Then again, I am not a self professed audio guru.
Click to expand...
Well, me neither... I guess best way is to record some sound with different levels, and then capturing and listening from your editing system...
 
this post should be a sticky....
i have learned more about the DVX audio in this post than seaching the whole audio section!
 
In digital recording, the very top of the scale is 0 db. If you go above that you will probably get distorted sound (just depends on how the manufacturer sets up the headroom, if any).

On the other hand when you use analog VU meters going to analog tape there is built-in compression going to tape so there you'd want to be pushing red most of the time.

The DVX audio scale goes from -34db to 0 db with -12db as the demarcation point before going in the "red". That means if you keep the input signal hovering around -12db you will have acceptably usable sound reproduced without distortion or clipping. Ideally, you want to have the hottest signal you can get (to improve signal to noise ratio) while just staying under the clipping/distortion point.

You can note that each red segment in the bar above -12 db represents approximately 3 db.

Every 6 db increase means the "apparent" sound level seems like it is twice as loud (to humans) - so that would be 2 red bar segments.

Depending on the DYNAMICS of the sound you are recording you could easily jump that 12 db space in going from a whisper to a mega scream or a gunshot, etc.

If you are just recoding ordinary dialog that does ebb and flow in volume, the 12 db will protect you from going straight to 0 db and distorting.

In cases where you know the dynamic range will be all over the map and sometimes at the peak or more, you'll need to introduce at least a limiter or compressor between the mic and the input to automatically knock down the signal before it pegs out.

So you both can feel satisfied that what you each have been doing has worked well for you and you don't really need to change the way you have been going about it.

If you want to MEASURE the dynamic range of the scene before rolling tape, you could just watch the meters on the DVX in rehearsal and adjust accordingly if they peak.

Ken
 
internal mic's have noise

internal mic's have noise

I've found that when using the internal mics I get a lot of static background noise, sort of sounds like a fan in the background, am i doing something wrong?
 
simphonicmedia,

It's hard to tell with out hearing what's going on or with out knowing the shooting location, but there are several things you can check quickly.

1) It's possible that you have the input gain (those little manual dials just below the LCD) turned up too high. Most mic preamps like to run in the middle of thier range to produce the lowest self-induced noise.

2) You might also be hearing the camera motor when shooting, but that shouldn't sound like "static". If this is the case, use an off board mic to test it. If by "static" you mean it's the same all the time AND that it sounds rotational in nature (like a fan), it may be just that. Definitely try on offboard mic and see what happens. Just keep the mic at least 3 feet from the camera and pointed away from the camera.

3) It could also concievably be wind noise if you're outside. Shoot something inside and you'll know right away.

4) If you are shooting inside it could also be the fridge, or the ventilation system.

5) Are you hearing it just in the onboard headphones or does the sound persist all the way through capture into the timeline in the NLE?

Ken
 
I just recently began using a boom mike with my dvx 100b and had no idea how to set the audio levels or channels. This thread has been helpful so far, except I still have one question... If I am going to keep one channel for the boom, and one for onboard(ambient) , considering I am plugging the boom directly into the camera, do the levels have to be set the same for both channels or does it even matter? Meaning my ambient noise wont be peaking at all, while the boom will be, so where does this leave me with the setting for the on board mike channel?
 
Agree on sticky

Agree on sticky

this is a most useful post. I have gleaned most of this info at this point from other sources, but these type of posts are the best b/c they really manages to pare down to the essence most of what you need to know to at least get acceptable use out of the cam. More use and trying out new things after you have the basics is where you "perfect" it I think.
 
bigteethproductions said:
... these type of posts are the best b/c they really manages to pare down to the essence ...
Click to expand...


OOPS - I meant "They really manage to" - just nitpicking myself for not editing the unnecessary plural of manage. :)
 
ezexpress,

You should adjust each channel separately according to what you see happening on the level meter. What you will be trying to do is get good level from each source (as close to or slightly in the "red Zone" 1 or 2 bars) as you can get depending on what you perceive as the likely dynamics of the signal.

This method assumes that you will be editing in an NLE that will further allow you to fine tune the volume balance bewteen the 2 inputs and pan both to your liking in the stereo field.

If you are not going to edit in an NLE then you should try to get the balance that sounds right in headphones plugged into the camera.

In any event, if your boom is for dialog then you will want it a little hotter (but not distorting) than your ambient, unless you really want the audience to hear the purple people eater sneaking up on the dialogers.

How much is a little? at least three db (one meter segment) or 6 db (2 meter segments) . 6 db is usually the threshold that lets all listeners discriminate the dialog easily. That's not to say you can't run 3 meter sements hotter. It's like salt and pepper to taste. Just remember that if you're going to run the onboard audio mic volume knobs higher than 2 o'clock, you will probably be introducing more self noise from them.

If you can't get the signal strength right at around 12 o'clock on those knobs, it's almost always better to get the mic closer to the talent so the signal to noise ratio goes up.

Please remember that just because it goes into the red zone on this camera DOES NOT mean it's distorting or clipping. In digital recording 0 db is the point where clipping and distortion happen, signal below that level is almost always clean. The highest signal level reached (the peak) CAN be in the red and not distorted on the DVX.



Ken
 
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Audio settings

Audio settings

Here's a trick i learned from a friend who is a boom operator. Use an XLR Y adapter to input a single (generally shotgun) mic into both inputs. When you sound check, set channel one with a good healthy signal (maybe hitting the red occasionally). Set channel two ( the other output of the y adapter) about 6 db lower. In this way, if you get a big dynamic peak on channel 1 that causes distortion, you have the same signal recorded on channel two, but 6 db lower, probably not distorted. Swap the distorted signal with the clean in post , adjust relative levels and viola, a healthy signal level with no distortion! This has saved my ass more than a few times, and besides, dialogue is rarely recorded in stereo, so use this trick to ensure against an unfixable audio track.
 
You don't even need a xlr y adaptor to do this. Just set channel one to input 2, and channel 2 to input 2. Plug your mic into channel 2 and it will go to both channels.
 
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