audio meter question
 

Hi there,
On a recent shoot I got some distorted audio (clipping). It shouldn't have happened, but I was using a second camera at the same time, and wasn't paying attention. Anyway, the end result is that I'm now a bit paranoid on the subject of audio.
A few questions:
- is there a bigger audio levels meter I can bring up on the EX-1 (as I used to be able to with another Sony camera, in the past)?
- the horizontal meters that I currently have in my display... am I avoiding distortion as long as stay to the left of the red (which is at the very right of the scale)?
- any other advice to someone who's been paying too much attention to pictures, and not enough to sound?
thanks, Malcolm

If you kept your levels under zero ALL THE TIME, you should be fine. Hitting zero will clip, so you need to keep the highs under zero. Average levels should be -20 or -12 at most with peaks at -3. This is different than analog systems where going over zero for some peaks was fine. Zero is death!

You might have had clipping in another part of the chain, perhaps the wireless or other source.

thanks for your reply, Ed.
With regards to this advice: "Average levels should be -20 or -12 at most with peaks at -3"
... I wish there were a meter I could watch which would show me these numbers/levels. I just have the little dotted horizontal lines in the bottom right of my display. Am I missing something?
Malcolm

Oh Ed... I meant to ask you what you meant about my getting clipping with my wireless mics. How can I check to see if these are the culprits?
Malcolm

(I've got the sensitivity set to -20db on my wireless mics)

To see larger audio meters, press the Status button and go to page #2.
You're not going to want to leave that display on all the time, but it is good to toggle on/off when necessary.

Also, may I suggest not running your mics straight into the camera? If audio is important to you, then investing in a decent field mixer is money well-spent.

Doug

I'm on -35 on mine, with the camera level at 5-7.

Very wise advice. A while back I invested in a Sound Devices 302 mixer, and I'm really happy with my audio, it's small enough to wear on my person, and it offers the ability to adjust and monitor levels away from the camera. The mixer sports excellent LED meters you can see in broad daylight and it also has a good limiter, better than the limiter you find on most cameras, so peaks are less of a problem.

The only cameras I'm comfortable using without a mixer are cameras like the Panasonic HVX200, HPX170, DVX100, etc. that have excellent audio input stages and handle over modulation more gracefully that most other video cameras. But that's another story. Most video camera designs treat audio as a second class modality, even though it's half of the picture.

thanks for your help, everyone.
Doug... I've got page 2 of the Status window memorized now, and will check it regularly.
Mike, I think I'll try your -35 setting.
Doug and David - I just had a look at the Sound Devices 302. Is there anything smaller, for less money, do you happen to know? I work by myself, and really have to stay mobile. With something like this, I guess the receiving half of my RF (which currently sits on top of my EX-1) would be attached to this mixer, and then this would feed (via XLR) into the camera, correct? It sounds like it might weigh/slow me down. Maybe that's a price I'll have to pay.
thanks for the advice,
Malcolm

Just for a contrary opinion. When I'm a one man band, I avoid carrying a mixer unless necessary or I am in a very sedentary situation. Just more gear to slow you down, more things to troubleshoot when there is a problem ( and there always is with audio.)

You should be able to get perfectly good audio by going directly into the EX-1.

If you are using only one mic directly into the camera, get a Y cord. Feed the mic to both channels with the Y cord and set channel 1 to "normal" levels and set channel 2 down 10% to 15% for protection.

You can accomplish the same thing by the proper setting in the AUDIO setup menu.

My sentiments exactly.

But should you need additional inputs from time to time and your budget very small, consider the Rolls pro-mix line (made in USA, believe it or not). The first unit arrived with a dead channel but replacement was swift. Audiophiles may wince at the thought of using a $120 field mixer, but it works great 2 years later (light duty) and the pots are still quiet.

Malcolm,

Although it's quite possible you have set your RF too "hot", I thought you might benefit from reading this thread:

The Skinny on EX1 Audio - DVXuser.com -- The online community for filmmaking

A gentleman nicked "Basspig" is giving a very sound advice on handling EX audio....

thanks again, everyone. Piotr, I'll read that right away. I will also be checking my levels carefully, and, when I can, setting different levels (one low one for safety).
Regards, Malcolm

Many times I also go straight into the camera when I'm in "ultra-portable" mode, however, sometimes I keep the mixer around my neck, a small inconvenience but in return I get better control ergonomics. Better limiter. Better metering. Three inputs. But yes, at a price: a little more weight and more wires. Always a trade off. I like the choice. As far as the price issue, I've not had a chance to try less expensive mixers in production. I chose the Sound Devices 302 based on the feature set, sound quality, ergonomics, and robustness. It's been dropped twice on a hard surface and other than the dents, there has been no impact on performance.

Bill... does this unit have easy-to-read LED meters? I looked at the picture on the web site and couldn't exactly see any.
Malcolm

No audio meters at all. Only a peak indicator light. For my purposes it's adequate as the EX1 provides metering capability, but for many situations this may not be the ideal option.

When in doubt, go with 12 oclock high.

Set your wireless mic, camera setting, etc. all straight up and down on 12 oclock, and 99% of the time you will be fine.

This is the simpliest rule to follow in the world of audio for those without audio recording experience.

Brian, do you mind explaining what you mean by this? I can understand setting my wireless to -35, for example; what do you mean by 12 o'clock, etc.
thanks, Malcolm

I leave my Electrosonic wireless mic transmitter, receiver, and EX-3 audio pointer to the very middle of the dial, which is the "12 Oclock" postion. My audio is alway great.

Would be nice if it were that simple, Brian, but not sure it applies here.

On my Lectrosonics receiver, there are no dials, so I need to go into the menu settings to set output level; the transmitter dial sits at about 2 o'clock; and the ex3's camera's audio pointer arrow is fixed at 3 o'clock, with the dial adjustable between 0 and 10. I've been leaving mine at about 6, but notice that basspig in the above-mentioned thread on dvx recommends 5 as optimal. My settings are for dialog in interviews or verite reasonably close-mic'd, using both Countryman condenser and/or Sennheiser shotgun.

Basspig's recommendation of setting it to "5" is based on the fact that your initial level/sensitivity settings are made in the menu for that particular mics' sensitivity or output level. The external dials are for fine tuning. Position "5" is the equivalent of "0", minus numbers cut the signal coming in and plus numbers give you a little more boost in case your talent/subject gets quieter than usual.

That's right, Dave. Except if I'm reading him correctly, he's recommending not going over 5, if you can avoid it, because of added noise.

Absolutely right....noise will go through the roof if you do that. It's best to think of it simply as a "trim" control.

Just noticed over on the other site that Mark (Basspig)) has adjusted his settings to 6, with atten at -35, which is also the setting I'd found was giving me best results.

Sony made this so confusing.

I recorded some fairly loud live music on the built-in mikes (formerly, I had supposed my external mikes were to blame... I am beginning to suspect my camera is defective in audio input function quite near the heart of the camera), getting peaks at 70% of the audio meter travel. Result: bad clipping. What are these meters intended to signify?

I have firmware 1.05

edit: I notice the worst clipping occurs during the quietest segments. I will post a video shortly showing this.

tone