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-   -   What am I doing wrong with Videomic? (https://www.dvinfo.net/forum/all-things-audio/117445-what-am-i-doing-wrong-videomic.html)

Brian Boyko March 20th, 2008 02:59 PM

What am I doing wrong with Videomic?
 
You know, everyone I've heard on the Web has said that the Rode Videomic is a very good videomic. But I've got one (mono) and - well, the noise floor is obscene - especially indoors - because I've got to turn up the gain ALL the way up on my camera in order to even hear the volume of the RodeVideomic.

And I have this on -0, which -should- be the loudest setting, right?

Or am I doing this in reverse?

Andy Wilkinson March 20th, 2008 04:00 PM

Do you have the newer version of the Videomic that has an additional attenuation switch hidden inside the battery compartment?

If so, what position is it in?

Steve House March 20th, 2008 04:06 PM

Quote:

Originally Posted by Brian Boyko (Post 845781)
You know, everyone I've heard on the Web has said that the Rode Videomic is a very good videomic. But I've got one (mono) and - well, the noise floor is obscene - especially indoors - because I've got to turn up the gain ALL the way up on my camera in order to even hear the volume of the RodeVideomic.

And I have this on -0, which -should- be the loudest setting, right?

Or am I doing this in reverse?

How's the battery in the mic? Check the DIP switches in the battery compartment - are they both all the way to the left? (Having one or the other to the right adds a -10 or -20 dB pad to reduce the level.)

"-0" setting on what?

What are you recording, how loud is it and how far away is the mic from the source? If it's normal speech, even a directional mic like the Videomic needs to be within about 2 to 3 feet of the speaker to deliver normal signal levels.

Brian Boyko March 20th, 2008 04:07 PM

Quote:

Originally Posted by Andy Wilkinson (Post 845815)
Do you have the newer version of the Videomic that has an additional attenuation switch hidden inside the battery compartment?

If so, what position is it in?

The position is in -0 - both all the way to the left.

Let me give you a link to an interview I conducted with the Rode.

This is probably the BEST of my Rode interviews, and you can absolutely hear the hiss on the bottom of the noise floor at 16:00. I recorded to a second audio source, and will probably use that, but still - I really wish I had recorded this with my $50 ATR55.
http://video.google.com/videoplay?do...59079644&hl=en

In fact, it sounds like... when I get home I'm going to get out a pin and start playing with those toggle switches. I mean, it sounds like someone wired those things in backwards.

Andy Wilkinson March 20th, 2008 04:25 PM

Videomic Hiss
 
Brian, I thought I'd seen something like this before. You might want to read this thread.....then again you might wish you had before you bought that mic for your particular camera. Don't shoot the messenger! :-(

http://www.dvinfo.net/conf/showthrea...=videomic+hiss

Brian Boyko March 20th, 2008 04:45 PM

Quote:

Originally Posted by Andy Wilkinson (Post 845833)
Brian, I thought I'd seen something like this before. You might want to read this thread.....then again you might wish you had before you bought that mic for your particular camera. Don't shoot the messenger! :-(

http://www.dvinfo.net/conf/showthrea...=videomic+hiss

I'm not too worried about buying it... the odd thing is that I've seen videos with the Rode Videomic.

Now, basically, the reason why I'm filming at -0db and not -10db or -20db is that when I turn the gain all the way up on the HV20 is the only way I can hear the Rode Mic. I don't want to go to -10db or -20db becuase that'll LOWER the volume, and make the noise floor even worse, right? Because I'm turning the gain up, I think this is what's causing the noise floor.

Worse still, it doesn't sound ANYTHING like the Rode VideoMic Test here: http://video.google.com/videoplay?do...arch&plindex=0

I'm glad I got seperate audio, but this is all very frustrating. I do NOT get this noise with the ATR55. :(

Maybe my Rode Videomic is just broken or something?

Steve House March 20th, 2008 04:56 PM

Quote:

Originally Posted by Brian Boyko (Post 845821)
The position is in -0 - both all the way to the left.

Let me give you a link to an interview I conducted with the Rode.

....

I hate to belabor the point but you HAVE to get the mic off the camera and up closer to the speaker. Not only does the distance you're working at mean you have to boost the gain and bring up the noise, the sound is full of room reverb and the clock ticking is driving me nuts. (You let the clock sit almost directly in the line of fire of the mic's pattern - next time stop the clock while you roll.) The softness of this person's voice is compounding the problem because you have to boost the levels so much to compensate. The 'inverse square' law applies here - each halving of the distance between him and the mic will increase the loudness of his voice 4-fold. Those loud thumps and bumps every time you touch the camera to zoom or whatnot are even more an issue than is the hiss. I recall you saying you're a one-man band and don't have a boom operator but in this sort of scene have you considered mounting the mic on a boom with whose other end is clamped to a c-stand? The mic should be angled at about 45 degrees from the vertical and pointed towards his mouth, just out of the top of the frame, a foot or so from him toward the camera. That'll eliminate the handling noise, reduce the clock ticking etc, reduce the hollowness from the room slap and because you'll be hitting the mic with stronger sound to begin with you can lower the gain and reduce the hiss and other noises.

Brian Boyko March 21st, 2008 12:15 AM

Quote:

Originally Posted by Steve House (Post 845850)
I hate to belabor the point but you HAVE to get the mic off the camera and up closer to the speaker. Not only does the distance you're working at mean you have to boost the gain and bring up the noise, the sound is full of room reverb and the clock ticking is driving me nuts. (You let the clock sit almost directly in the line of fire of the mic's pattern - next time stop the clock while you roll.) The softness of this person's voice is compounding the problem because you have to boost the levels so much to compensate. The 'inverse square' law applies here - each halving of the distance between him and the mic will increase the loudness of his voice 4-fold. Those loud thumps and bumps every time you touch the camera to zoom or whatnot are even more an issue than is the hiss. I recall you saying you're a one-man band and don't have a boom operator but in this sort of scene have you considered mounting the mic on a boom with whose other end is clamped to a c-stand? The mic should be angled at about 45 degrees from the vertical and pointed towards his mouth, just out of the top of the frame, a foot or so from him toward the camera. That'll eliminate the handling noise, reduce the clock ticking etc, reduce the hollowness from the room slap and because you'll be hitting the mic with stronger sound to begin with you can lower the gain and reduce the hiss and other noises.

Well, the final version is going to use audio on a Zoom H2 which was recording out of frame. It's about 2 ft. from the speaker. I suppose you're right about the inverse square law. As for the loud thumps and bumps, I'm well aware of them. I wasn't the cameraman for the shoot. My director of photography was, I-sh*t-you-not, arrested for terrorism. (Bogus charges, most of them eventually dropped.) So the cameraman is my PA.

Weirdly, though, I understand the idea of getting people closer to the mic. I don't think that would have helped. The mic is about 3.5 feet away in that shot. It's just that NZ speakers are very, very soft. It was driving me nuts how softly people spoke in New Zealand.

You're right, a C clamp and boom mount would have been better, but - and this is a big but - I was working under a number of limitations.

First, my cameraman was arrested for terrorism, so what was a 3 man crew became a 2 man crew. Second, in some cases I literally had all of 3 minutes to set up or I lost the interview - completely. Camera mounted-shotgun doesn't seem so bad compared with nothing.

Third - I have another audio source for that interview. It's better. I'm going to use that. Still, it would be nice to have a bit better sound.

One final thing - I tested out the Rode at home, flipping those attenuator switches. And once I did, I could hear a distinct difference - even at -0db. Maybe those switches were funky in some way and needed to be set at -0db, that they were somehow in the middle? Who knows.

Eventually I'm going to get a Beachtek and an XLR mic anyway, I just wanted to use the best I've got if I can, if I should need it before two paychecks from now.

Steve House March 21st, 2008 01:25 AM

Camera op arrested for terrorism?!?!? ROFL - that's one for the textbooks!

Don't know about those in the Rode mic but those tiny switches can appear to be in one position when in fact they're in the other. With a tiny screwdriver or a probe of some sort push them fully to the right and then back again to the left, maing sure you feel a distinct 'click' of them going into position.

Your camera perspective sure looks like you were a lot farther then 3 feet from the subject.

Have you considered using a hard-wired lav in these sorts of interviews? With a seated subject there'd be no need to go to the expense of wireless.

Roger Averdahl March 21st, 2008 04:07 AM

Brian, the real problem with hissy audio is the camera itself, not the microphone. Hissy audio is a well known issue with the HV20 and the hiss is present with whatever microphone you will use with it. As you have noticed it is very present in quiet situations.

Yes, all cameras audio are hissy but the HV20 stands in its own class...

Its sad because the image the camera deliveries is really great.

Brian Boyko March 21st, 2008 07:54 AM

Quote:

Originally Posted by Steve House (Post 846043)
Have you considered using a hard-wired lav in these sorts of interviews? With a seated subject there'd be no need to go to the expense of wireless.

We actually tried that with former prime minister Jenny Shipley. As it turns out, we didn't get any audio from that and after that, learned to distrust the lavelier mics.

I'm actually selling off my spare camera in order to get some better audio equipment, but I'm trying to figure out if my Rode was somehow junk.

Brian Boyko March 21st, 2008 08:00 AM

Quote:

Originally Posted by Roger Averdahl (Post 846068)
Brian, the real problem with hissy audio is the camera itself, not the microphone. Hissy audio is a well known issue with the HV20 and the hiss is present with whatever microphone you will use with it. As you have noticed it is very present in quiet situations.

Yes, all cameras audio are hissy but the HV20 stands in its own class...

Its sad because the image the camera deliveries is really great.


I did notice that when you turn the gain up, the hiss notably goes up. The problem, I think, in this case, was that I constantly had to turn the gain all the way up in order to hear anything. I'd agree with you that I'd need to get closer - and some interviews where I'm right in the person's face, the audio is great - but because the actual volume output from the Rode Mic into the camera seemed extremely low, in order to get any sound, we turned the gain up and up comes the hiss.

This was not a problem with the ATR-55. It may very well be that I've managed to fix this problem. In the meantime, I do have the backup audio, and next movie, I'll get a real crew.

Oh, and the guy arrested for terrorism - it's nuts, but there's no way I could have predicted that. First of all, New Zealand doesn't have terrorists. At least, not since the Rainbow Warrior bombing. Second, he had a completely clean criminal record.

When you're running around New Zealand with a two-man crew, your equipment dragged from the U.S. on a budget because the same stuff is prohibitively expensive over there... you make do, sometimes.

Roger Averdahl March 21st, 2008 08:13 AM

Quote:

Originally Posted by Brian Boyko (Post 846140)
...but because the actual volume output from the Rode Mic into the camera seemed extremely low, in order to get any sound, we turned the gain up and up comes the hiss.

Brian, have you tested the Rode with another camera? The VideoMic is a very hot microphone and thus give users the opposite problem - distortion. If you have access to another camera (not HV20/HV30) i would try it and see if the mic indeed has low output. A long shot is that it may be a mis match between the Rodes impedance and the cameras impedance.

What about the battery in the mic, is it a new fresh one? Changing to new fresh batterys really makes i difference so its really worth trying it.

Brian Boyko March 21st, 2008 12:20 PM

Quote:

Originally Posted by Roger Averdahl (Post 846148)
Brian, have you tested the Rode with another camera? The VideoMic is a very hot microphone and thus give users the opposite problem - distortion. If you have access to another camera (not HV20/HV30) i would try it and see if the mic indeed has low output. A long shot is that it may be a mis match between the Rodes impedance and the cameras impedance.

What about the battery in the mic, is it a new fresh one? Changing to new fresh batterys really makes i difference so its really worth trying it.

Battery was fresh. Weirdly, I tried out both the VideoMic and the ATR55 and side by side after I had started fiddling with the switches. I know it's subjective but I couldn't tell the difference in audio quality.

If it's not something weird with the switches, Maybe the ATR 55 has a longer "reach" than the VideoMic?

Steve House March 21st, 2008 02:01 PM

Quote:

Originally Posted by Brian Boyko (Post 846252)
Battery was fresh. Weirdly, I tried out both the VideoMic and the ATR55 and side by side after I had started fiddling with the switches. I know it's subjective but I couldn't tell the difference in audio quality.

If it's not something weird with the switches, Maybe the ATR 55 has a longer "reach" than the VideoMic?

There's really no such thing as 'reach' even though it's a commonly used term. The Rode is actually MORE sensitive and has a higher output at a given SPL than does the ATR55, rated at -38dB @ 1Pa compared to the 55's -45dB @ Pa in tele mode, -55dB @ 1Pa in normal mode (less negative means higher output for a given sound level). Though A/T hasn't published the polar pattern on their web site, I'll bet that depending on the mode you use it in, the ATR has a wider pattern than the Rode - certainly it does in the 'normal' mode and maybe in the 'tele' mode as well. Maybe the effect you're observing is a result of Rode's tighter pattern giving rise to more critical aim requirements to keep the subject within the area of maximum sensitivity. I keep thinking of that clock tick in your sample video - that was picked up very well, very loud in the track, and yet it was more distant than the subject and I doubt it was louder than his spoken voice. Perhaps it was spot-on in the middle of the pattern while the subject was partially out towards the edge. Might be worth plugging the Rode into a headphone amp, putting on a set of cans, and exploring the environment to see how its levels vary with aim.


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