Rode videomic + Zoom h4n = problem HELP?

[LDS]

First.. this is my first post so WELCOME TO ME...

now... I have just tbought new Zoom h4n and I am having ridiculous problems with it when trying to connect my Rode videomic (no not the Rode NTG-2 but the cheaper videomic) it is connected via 3.5mm cable

I am having annoying buz when recording:

samples: https://soundcloud.com/user5353041/zoom-test-080101-010
the rec level is
Rec Level - 66
-12

does anyone know what's the problem? how can I fix it? Any help please?

 

[Alcove Audio]

I'm not hearing a buzz, I'm hearing a hum; sounds like a 60 cycle hum, but it's not quite 60 cycles, probably because it's the UK and not the US. It could be a refrigerator, dishwasher or other appliance, or could be a grounding issue if you are using the AC adapter instead of running it on the batteries.


Are you plugging it into the 3.5mm mini-pin input?

Do you have fresh batteries in both units?

Are you getting the mic in really close?

Do you have an extension cable on the mic?

Is your computer off?

Is your cell phone/PDA/whatever off?

Is the HVAC off?

Are all the appliances off?

Are you using the AC adapter instead of running it on the batteries?


BTW, the VM is a Hi-Z (high impedance) device, so it will be very prone to all sorts of EM and RF interference.



Welcome to the world of audio troubleshooting!!!

 

[LDS]

Hey to answer your questions:

Are you plugging it into the 3.5mm mini-pin input?
YES

Do you have fresh batteries in both units?
YES - I use rechargable and I tried bot ways.. still "Hum"

Are you getting the mic in really close?
YUP - ABOUT 12 INCHES

Do you have an extension cable on the mic?
YUP ABOUT 2METERS

Is your computer off?
NOP - it's not off... When I film I film with a lot of equipment on, chargers, lights, laptops etc... So I don't understand why does it effect... I am not living on a desert how are those guys who film in live venues - they film with speakers plugged in gitars lots of light and dont seem to have my problem?

Is your cell phone/PDA/whatever off?
NO - not off and again.. why should it be?

Is the HVAC off?
Don't have it

Are all the appliances off?
[b[]o[/b]

Are you using the AC adapter instead of running it on the batteries?
tried both ways


again I dont really understand why should I have everything around me off? I do film short film I use light... sometimes I film in a kitchen and cant switch off frizer for the whole day.. I thought for the money I wouldnt have any problems.. I am getting better sound when I conect my videomic to my canon 60d...

 

[Alcove Audio]

I dont really understand why should I have everything around me off?

You turn everything off to find out what is causing the hum. Then you turn them on (and back off) one at a time to see if you can find out which unit is causing the hum. Sometimes it is a combination of things that causes it.

Is the HVAC off?
Don't have it

You don't have Heating, Ventilation or Air Conditioning (HVAC)?

Are all the appliances off?
no

They are quite often the main offenders.

Is your cell phone/PDA/whatever off?
NO - not off and again.. why should it be?

Is your computer off?
NO - it's not off...

Because they can generate Radio Frequencies (RF interference) and ElectroMagnetic impulses (EM interference) that can be picked up by recording devices.

Do you have an extension cable on the mic?
YUP ABOUT 2METERS

This is acting as an antennae picking up all the stray RF and EM interference in the area.

how are those guys who film in live venues - they film with speakers plugged in gitars lots of light and dont seem to have my problem?

Because they are using balanced/grounded Low-Z (Low Impedance) equipment, and you are using unbalanced ungrounded Hi-Z (High Impedance) gear.

I am getting better sound when I conect my videomic to my canon 60d...

Have you tried plugging into the H4n without the extension cable?

 

[AudioPostExpert]

again I dont really understand why should I have everything around me off? I do film short film I use light... sometimes I film in a kitchen and cant switch off frizer for the whole day.. I thought for the money I wouldnt have any problems.. I am getting better sound when I conect my videomic to my canon 60d...

Just in case you're not joking, I'll explain:

1. Every bit of equipment you have mentioned produces noise when switched on. It doesn't matter how much you spend on equipment, if you've got a noisy environment you are going to have noisy recordings. If you were to buy the best, most expensive mic, mixer and recorder on the planet all you would accomplish is a cleaner recording of your dialogue, freezer, computer, lights, etc. Your production sound recordings would still sound at best amateurish and at worst unusable. Audio equipment is not intelligent, it doesn't know what you want to record and what you don't, it will just record whatever is in the recording environment. So you need to make sure as far as possible that the only sound in the recording environment is sound you want to record.

2. All electrical equipment radiates electro-magnetic interference and mobiles, computers and other electronics also often radiate Radio frequency interference. Both of these will degrade the quality of your recordings, again commonly to the point of the recordings being unacceptable/unusable. A balanced mic will help to solve this problem, here is why. BTW, live events always use balanced systems but even so EM and mains hum are still frequently a problem which needs solving. Again, by far the best solution is not to have any (or to have as little as possible) of this type of interference present in the first place by turning off everything which isn't absolutely essential!

G
EDIT: Must have just started writing this as alcove posted, 2 for the price of 1!

 

[knightly]

The worst offenders for creating RF and EM are things with an electric motor. The magnet + electromagnet circuit used to move them is an RF/EM generator. This includes the fan in your computer/laptop, the compressor in the fridge and the ceiling fan. The phone is specifically an RF transmitter -- enough said there.

 

[LDS]

Hey guys... Well I am no audio guy so I am/was bit confused...

Thanks for your help tho.. I figured it out now... All I have to do is use batteries not the AC Adapter...
It is bit confusing as well when I use headphones while recording because I can hear the HUM in my headphones but then when I conect it to the computer I hear no hum... strange...

also does anyone know best settings to record audio using video mic for short films?... Just asking as, as I said I am no audio guy



P.S. meanwhile if you have nothing to do please check out my work
http://www.youtube.com/user/DiSparrowFilms

 

[Alcove Audio]

All I have to do is use batteries not the AC Adapter

I mentioned that in a previous post...

Are you using the AC adapter instead of running it on the batteries?

You probably had a ground loop caused by the AC power or an appliance was creating a hum in the AC system.

...also does anyone know best settings to record audio using video mic for short films?...

Unfortunately there are no "set it and forget it" solutions. You will have to experiment. You will have to find the loudest settings for the VM and H4n for each situation that gives the minimal amount of self-noise (usually hiss) and that do not distort. After a while you will get to instictually know a basic starting range for each situation. That's what becoming proficient with your gear is all about.

BTW, who is swinging the boom and monitoring the audio for you while you are shooting?

 

[LDS]

BTW, who is swinging the boom and monitoring the audio for you while you are shooting?

Believe it or not but I am in charge of every single bit on my short films... I sometimes act as well so I have to concentrate and set first the lights, then show people who never had camera in their hands how to work the camera and what angles I want then show another guy who never had boom in his hand how to use it then back to directing my actors/co-actors and getting back to my character... by the end of the day I can easily get locked down in Psychiatric hospital

I started from acting but then Being a foreigner in the UK is like GOOD LUCK so I have decided to spend money on my own equipment and start doing my own things thats why I sometimes have no idea about some equipment.. I got the h4n few days ago so it takes me time to get to know my gear...

 

[knightly]

I started there too... you'll quickly learn that you want more people... but I feel you have to experience why to really move forward... so when you get to have someone dedicated to swinging boom on their second piece with you, you'll REALLY appreciate what they do for you and give them much more of your valuable time on set.

 

[LDS]

I started there too... you'll quickly learn that you want more people... but I feel you have to experience why to really move forward... so when you get to have someone dedicated to swinging boom on their second piece with you, you'll REALLY appreciate what they do for you and give them much more of your valuable time on set.

the problem is to find them... I work with friends... But they have no clue how to use it all...

 

[Alcove Audio]

the problem is to find them

You work on the projects of other people and they will (hopefully) return the favor. Filmmaking at every level is about building your network.

 

[knightly]

The more they use it, the better they'll get... especially if they take each task they're doing really seriously.

 

[AudioPostExpert]

... so when you get to have someone dedicated to swinging boom on their second piece with you, you'll REALLY appreciate what they do for you and give them much more of your valuable time on set.

Very good advice. In fact this was one of the benefits of the old studio system. If you applied for a job as say a cameraman, for your first several months you had to do a number of rotations with different departments before you were allowed anywhere near a camera! A month or so with the sound department, maybe props, lighting, electrical, costume, etc. When you actually got to touch a camera, you had a good appreciation of the difficulties facing the other departments. In those days it was common to see a cameraman trying to operate a camera under a sound blanket, so the noisy film camera didn't spill into the production sound but those days are long gone. There is simply little or no consideration for the other crafts among the vast majority of professionals these days. Today, a DOP, cameraperson or even a director will simply blame the production sound mixer for noisy dialogue, regardless of the fact that a little planning or consideration on their part could have avoided/solved the problem.

G

 

[harmonica44]

It's the same thing with me. I am helping getting an indie film made by a local filmmaker who is borrowing a lot of people for his crew. I am trying to get the sound right, but he blames me, even though he chose locations with noisy ventilation that he is not allowed to shut off.