What is this **** beeping?
 

This is a clip taken from an office scene with overhead fluos, shot on an XL2 with an AT4073a and an AT40xx. I do not remember which channel is which.

Is it cell phone traffic? Whatever it was, neither the cameraman nor the boom operator heard it.

I'd almost describe it as a 'squeaking'.. More like a mechanical noise than an electronic one. Might be tape transport problems?

You think so? Would cleaning the head have helped? It did not happen in every scene, despite the fact that we used the same equipment. Perhaps it got worse over time?

To me, it sounds electronic. In particular, interference from something that is either transmitting an RF communication signal (wireless network, cell phone etc) or something digital operating at high frequency and with poor shielding (such as a computer).

Does it occur in specific locations in the office(s)? If so, it may give you a clue.

I can understand why it was detected during the shoot - it is very weak.

There were computers with LCD screens running nearby (it was an office scene, after all).

However, it also happened in other scenes featuring the same actor, so I think my cell phone hypothesis might be right.

Sounds very plausible. It reminds of when I have been on a conference call in a conference room with a wireless speakerphone, I would occasionally hear some beeps quite similar to yours and someone's cell phone would ring. It got to the point that I would say "Your phone is about to ring...."

My guess is that it is the cell phone talking back to the tower when the network is trying to establish a connection.

Now that I think about it, I can sometimes hear my girlfriend's cell phone do the same thing over her web camera. Why do microphones make it more audible?

The bad thing is that I already did a dubbing session with the actor and he probably had his cell phone on again :( The good news is that we have more dubbing sessions lined up, so I will sure to ask everyone to turn off their cell phones.

How do big productions cope with this problem?

That didn't sound like a cell phone to me. They usually produce a "brraaaap braaaap braaaap" kind of sound when they phone home. It sounds to my ears like something flowing through a pipe somewhere, maybe a noisy coolant pump in the air conditioning system. I hear it under a whirring-humming sound that definitely sounds like HVAC so I'd suspect it's also a part of the noise from the air conditioning system

They put in the contract that any powered-up cell phones within 100 yards of the location will be summarily destroyed <grin>.

Agreed. I'd know that sound anywhere; my CA sounds just like it--especially noticeable at night when I can't sleep. :)

Except there was no air conditioning in one of the locations.

Hi Emre......
 

Well, I've listened to that clip 20 times and thought it familiar, then I read your comment about "office scene" & "computers with LCD screens" and then it hit me - that sounds like the mute but distinct sound of an office chair return spring under load - like when you tilt back in the chair and then roll forward again - were there any within a bulls roar of the shoot and more to the point - were there any bums on one?

CS

You might also look for something a little less sophisticated. It doesn't sound electronic to me and it definitely doesn't sound like cell phone carrier being picked up by your equipment.

Does your soundperson have hanging earings? Or a noisy necklace? Or is there a loose bolt somewhere on your tripod/jib/crane? Were there two glasses on the desk that were just touching each other? Did one of the computers have a key hanging from the back of it? Or one of the crew have keys ? Was there a cat in the room? Don't laugh ... it's all possible.

The sound seems random, although the clip is short so there may be a pattern that isn't complete yet. But what I hear is mechanical and probably something inane.

Remember, you are the only one thinking of every possible scenario and problem during a shoot. The crew are just there for the food. So a soundperson wearing earings, necklace and charm bracelets wouldn't understand why they should be a problem.

Anyway, run the entire audio clip through a good editor that has noise reduction and that will suck it out of there.

My two cents ...

Tim

One final question. Were you using a 16xmanual lens in these shots?

Chris: There were office chairs, and people were sitting in them.

Tim: You are right that no-one thinks about it as much as I do.

Richard: We used the stock lens.

Here is another clip taken at another location and date. The only thing in common is one actor, the crew, and the camera. No air conditioning, fluos or office chairs; it's a bedroom scene.

I thank everyone who has contributed. Together we make a great team!