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Dialogue recording in a helicopter


Tapio

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We will have to record a scene in a moving helicopter this saturday and I was wondering if you guys here have experience or any advice regarding sound recording in that kind of an environment.

It's a scene for an entertainment show (very similar to BBC's Top Gear) and therefore very much unscripted (which means ADR is not an option). The two talents will try to fly a helicopter with the help from a flight instructor on board.

The helicopter used on saturday is Robinson R44 and there are only four seats. So after two hosts and the pilot there is only room for our cameraman.

(I will be in a second helicopter that films and tracks the first one with our hosts onboard.)

Our plan at this point is to put SD 442+744t in the cabin and place a wired lav mic inside the cameramans headset. All three will also be wired with Lectro SMDB's for the dialogue that happens before the engines are started and background noise becomes too loud.

I asked the helicopter pilot if we could tap into their intercom system but apparently there are no outlets left when all four headsets are in use. That's why we'll have to use the wired lav... unless someone has any better ideas? :-)

I have no problem using dialogue that sounds like a typical intercom / telephone sound. It actually feels quite natural in this context. I'd just want our voice track to be as clear as possible.

-Tapio

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" tap into their intercom system "

Remote Audio makes an adapter for that...(2nd time today!!)

-- the aviation comm connector is not one of our typical connectors--

or the Lav in the headset.

" ADR is not an option "

Actually, it is! you won't be able to see their lips well, and you could rerecord any conversation later...

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Remote Audio makes an adapter for that...(2nd time today!!)

-- the aviation comm connector is not one of our typical connectors--

Yes. The pilot mentioned that they call it "NATO connector". It propably is and looks very similar to the one that Remote Audio sells.

Our only Remote Audio dealer doesn't have it in stock though..

" ADR is not an option "

Actually, it is! you won't be able to see their lips well, and you could rerecord any conversation later...

Technically yes, but not with our scheudule (not to mention the talents' schedule!) and budget.

I've done the "lav in the headset" trick twice before and it sounded ok. The cable splitter is a good idea too! We'd just have to find the Nato plug somewhere in order to manufacture a suitable cable.

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" with our schedule "

preproduction planning...

another dying practice.

This is a show that involves celebrity guests, a different one in each episode. If the person we want has only one available day the whole month and even then only three hours for us (of which we will film 2,5 hours), I'd like to know how we could fit in an ADR session. Therefore we sometimes have to approach our setups and situations like they were reality or documentary shoots. We will have to "nail" almost everything on the first time.

(I can however ask our sound mixer to do a site survey at the airport before saturday and do a test recording.)

I'll ask our production manager to be in contact with you for consultation before we start planning the next season.. ;-)

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" Therefore we sometimes have to approach our setups and situations like they were reality or documentary shoots. "

nothing personal, but when did they book the guests (2), and when did they hire the chopper ???

that is when an experienced producer and/or UPM starts plannning for and solving the problems. Unfortunately today that professional behavior is going away, and fast. just for examples, when booking the chopper, they could have inquired about getting the audio. actually lots of choppers available for rentals have recording capabilities built in, as tourists who take sightseeing flights frequently want to plug in and record. likewise they could have alerted you earlier, you could have been on the phone or email to either an avionics source or Remote Audio, and gotten what is needed in motion in plenty of time. Whereever you are, I'll bet a proper recording tap, or at least a plug, is available to you either by pick-up, or by 2nd day, or maybe even next day delivery.

"I'll ask our production manager to be in contact with you for consultation before we start planning the next season. ;-) "

OK

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" Therefore we sometimes have to approach our setups and situations like they were reality or documentary shoots. "

nothing personal, but when did they book the guests (2), and when did they hire the chopper ???

that is when an experienced producer and/or UPM starts plannning for and solving the problems. Unfortunately today that professional behavior is going away, and fast. just for examples, when booking the chopper, they could have inquired about getting the audio. actually lots of choppers available for rentals have recording capabilities built in, as tourists who take sightseeing flights frequently want to plug in and record. likewise they could have alerted you earlier, you could have been on the phone or email to either an avionics source or Remote Audio, and gotten what is needed in motion in plenty of time. Whereever you are, I'll bet a proper recording tap, or at least a plug, is available to you either by pick-up, or by 2nd day, or maybe even next day delivery.

"I'll ask our production manager to be in contact with you for consultation before we start planning the next season. ;-) "

OK

I appreciate your reply and all other contribution on this board too, but it would help if the fact that not every production in this world is located in Hollywood, or even in the USA for that matter, would be kept in mind.

In my country we only have a couple of helicopter vendor companies and any helicopter sightseeing is nearly non-existent business here.

And that goes with the budgets as well. Our whole 12 episode season propably has smaller budget than what a single episode in the US (or UK) would cost. We'll have to do with what we have available to us.

Thank you Bob for the plug type number! I posted a message on a local aviation related forum and will call the (nearly only) two aircraft repair shops here tomorrow (it's midnight now).

In this show we have one permanent host and one celebrity guest that changes in every episode. The whole season was filmed already this summer - except for this one "guest star" segment. And this extremely busy guest told us yesterday that he's suddenly available on saturday for approximately three hours. Not much planning time left but we'll do our best.

Real life doesn't always go like in the movies.. ;-)

I'll try to arrange the adapter cable for our sound mixer(s) and then we'll also have the backup plan with the wired lav.

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A splitter cable is the best option by far if all the outputs are used, after that, a lav in the headset will work, you know that already. It won't sound as good, but you're in a helicopter and it needs to sound like you're in a helicopter, so go with that if you have to. I've worked a lot in helicopters and the splitter cable, or a dedicated headset is my preferred optio, but a well placed lav works too. Most aviation suppliers will have the right plugs, they're easy to solder, make one if you have time.

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Don't get on that helicopter!

Heh, I won't! :) I'll be filming them from another helicopter.

And thanks Jon! Bob already posted the TRRS connector pin order, but if I wanted to make a U-174/U to XLR male cable, how should I wire it in the XLR end? That signal most certainly isn't balanced... any ideas?

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Heh, I won't! :) I'll be filming them from another helicopter.

And thanks Jon! Bob already posted the TRRS connector pin order, but if I wanted to make a U-174/U to XLR male cable, how should I wire it in the XLR end? That signal most certainly isn't balanced... any ideas?

For headphone monitoring, XLR3M unbal would be (Gnd) pin 1 and pin 3 = -, pin 2 = +

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You will need to pad down a NATO plug feed by about 20dB to dynamic mike level

Quality is comms quality but sounds right for in-flite dialogue

Further info below:

-

.

>\

>

>Re: Aviation Headset Feed.

>

>

>There are two connection formats;

>

>1- NATO plug (U-174) which is a stubby 4 connection jack

> on which the headphone feed is connected as follows

> First ring back from tip of plug is 2 and is live

> Third (rear) ring back from tip is 4 and is earth

>

>2 - Two jack general aviation system which uses:

> Standard 1/4" mono jack for headphone circuit (M642/4-1)

>

> 3 connection jack for microphone (M642/5-1)

> This is similar to a British Post Office Type 316 jack

>

> (Bracketed numbers are David Clark Co Inc part numbers)

>

>My advice is to buy a U-174 NATO plug and wire connections

>2 and 4 each with a 10K resistor in series to pins 2 and 3 of

>a male XLR3, and solder a 47 ohm resistor across the XLR3

>pins 2 and 3 to pad to signal down to dynamic mic level.

>

>Also buy a converter lead which will accept the NATO plug

>that you have wired, so that you can connect into a system

>which is wired with the alternative 2 jack general aviation system.

>

>Then you can take audio feeds from either type of system.

>

>The converter lead is a David Clark p/n 18253G-05

>or alternatively a Sigtronics p/n 900051

>

>The above is the simplest way of doing it.

>I used this approach whilst servicing Cousteau expeditions.

>

>Other wise you can buy a intercom box like a Sigtronics Trancom 2

>which provides an auxiliary audio output, which you would still need

>to pad down and interface with your XLR3 balanced mic level input.

mike

>

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I know this reply is late already, but I always place a lavalier mike - Tram TR 50 or Sanken COS-11 - togheter with the helicopter's headphone's mike, under the foam cover they usually have.

I use very small black cable ties to have the lavalier mike's black cable running down the helicopter's headphone's mike flexible arm into a wireless tx.

It looks like it's another wire of the helicopter's headphone mike, nobody ever complained!

And if you place the lav's cable in the hidden side of the flexible arm it almost doesn't show.

You've got to carefully adjust cables, input levels and lav mike's position, but this has always worked very well for me!

Tony Muricy

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A couple of things: be careful about referring to this radio/intercom plug as a NATO plug, as this is not it's official designation. I've been dealing with this coonector for 15 years now, and this thread is the first I've seen the term used. That said, it is the commonly used for military aviation radio/intercom headsets (both helicopters and fixed-wing), and connects both talk and listen with a single connector. However, while it is also the connector of choice for civilian helecoptors, it is not usually found in civilian airplanes, which use a 1/4" TS plug for listen, and a very odd TRS plug (about 3/16") for talk and mic keying.

Also, as mentioned earlier, it is usually required to drop the level in the cable by about 20dB. There is a wide range in this "about", though, because most military headphones have 8 Ohm drivers, and most civilian headphones have a higher impedance. The level coming to your mixer can vary alot from job to job because of these and other variables, so don't be surprised when you need to adjust your input trim for different aircraft.

Glen Trew

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I'm back from the film shoot in one piece! :)

It all went really well. We ended up using Lectro SMDB's with DPA capsules on all three for the dialog happening before engine startup and after landing.

For the intercom we placed a wired lav mike inside the fourth headpones (our b cam op was wearing them) and also a line feed from a split cable. Line feed was connected directly to camera and the other four (3 wireless and the lav for intercom) into 442 and then 744.

I managed to get the correct cable from an airplane equipment vendor via courier on friday.

And the weather was great too! :) Thanks to everyone here for your help and suggestions!

Justan: if I'd have to compare the show to something more familiar, I'd say it's closer to that one very famous and very expensive show on BBC.. ;-) Except that our crew and budget is maybe 1/8 of what they have.

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