Audio Distortion problem?

P

ProAction Films

New member
Equipment used.

HVX200
Brand new Sennheiser G3 Wireless Lav (first time using it.)



I just recently shot a small interview and I set my audio levels and they looked fine (forgot my headphones stupid me...)

I'm going through the footage and I'll explain it as best as I can, If you closed your eyes and just listened to it, it would sound like the levels are really hot but its not loud and when the person says something like "your" the U-R gets distorted, but when I look at the meter in FCP its showing -20 db. And when I set the levels in camera, they were fine, no where near peaking as well as on the receiver pack the little LCD screen has a meter as well and it was also fine.

I can't figure out why it sounds like this. I've played with some filters but can't seem to get rid of it.
 
It sound like you had the Sennheiser's output level set too high and it overdrove the audio circuit and clipped. Check the AF Out setting. I think I keep mine at -4, which works out to around mic level. If it's at +12 or higher it will be closer to line level, and distort if you don't set your inputs to line. Also, always wear headphones!
 
It's hard to say what happened here as there are a number of things that could have caused this.
1. your mic input was to hot on the transmitter
2. your receiver output was to hot to the camera
3. Your camera is jacked

What I do know (as someone that cleans a lot of bad audio) is that there is very little that is salvageable in there. You have just learned a valuable lesson as to why you should always wear your headphones. (and why you should have a backup system)
 
Low batteries might also be a culprit. Something was overloading either because levels didn't match or because power was low or? Bad connection would also be a possible. It also sounds really compressed but that may just be YouTube.

As Thesoundguy said there is not a lot you can do to salvage this. It's distorted everywhere it's just more noticeable where you point it out. Streight clipping is actually a lot easier to "fix".
 
With a cable mic (not radio, that is...) you basically need to set the levels only in one place, either camera, or mixer (and have the mixer and camera levels correctly aligned, of course). With G3 there are two places where the levels have to be set correctly, and the receiver to camera send level also correctly set. Three possible settings to screw up instead of one.

1) Level on the transmitter. This is like the normal level setting with a cabled microphone, except that there is just 10 dB steps (??? I have only the G2) and that you can not ride the gain during the take.
2) the output level of the receiver can be adjusted from low, mic level output to high level line strength signal. If this level is too high and you use mic-in on camera, there will be distortion. If you have this set too low and try to use line-in on camera, you will get noise.
3) finally you need to set the levels on the camera. It is possible to set levels safely low, but still get distortion from stage 1 (transmitter clips) or 2 (line level signal oversaturates the mic level camera input).

All components should be set correctly before the shoot, it is very easy to get some setting wrong in a stressful situation, similar things have happened to me also with G2 sets. For this reason I try to avoid using radio mics and rather use cable if the person does not move around during a take. Less possibility of having some setting wrong, and better sound quality also.
 
If I might add, assuming you are going mic level, go into camera menu and change audio sensitivity to -50dBu from -60dBu if you haven't already done so.
Make sure phantom power is off.
 
I agree with Noiz2 that a low transmitter battery could very well be the prime suspect. My practice is to always use fresh batteries for each session.
Note also that (depending on the battery chemistry) some rechargeable batteries don't produce sufficient voltage for critical applications like wireless transmitters, even when fully charged.
 
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