View Full Version : Sound from an aircraft cockpit


Mike Benjamin
April 25th, 2005, 04:24 AM
Hi,

Can anyone tell if there are any special ways to record sound through the XL1s in a general aviation aircraft. I will be sitting next to the pilot and have access to the headphone socket (1/4 inch jack).

Jimmy McKenzie
April 25th, 2005, 06:11 AM
The 1/4 inch jack will be headphone impedence and will be tough to get a non-distorted feed to the XL1. You could rig a small mixer and bring the feed in that way and then line out from the mixer to the XLR adapter on the XL1. But that's a bunch of kit in a small cockpit. You could also use a lav mic placed in the earphone of the aviation headset and record wireless to a camera mounted receiver. Be to to record plenty of ambient cockpit noise with no extraneous sounds. Then in post, you will have a dialogue track as well as sound floor to mix.

Mike Benjamin
April 25th, 2005, 06:49 AM
Thanks Jimmy! If I have a lav mic in the mic area of the headphones I won't pick up incoming radio, only what is said by the pilot. I can use the MA200. By switching the mic to att or line, will that help the distortion?

Mike

Tony Davies-Patrick
April 25th, 2005, 06:54 AM
Some good ideas there, Jimmy. I'll be doing the same next month, but I'm not sure whether we're going to hire a helicopter, light plane, or microlight.

Hopefully I can get the pilot to leave the door open during the flight (so I don't have to film through thick glass). It might be worth, as you have mentioned, plugging in a wireless mic to my XL1s and place the clip mic not in the pilot's helmet, but in my own, as this would allow more control over the dialog I want to convey on tape.
I could also switch on the camera shotgun mic (with wind sock) and manually adjust input until it's quite low, just to add some ambient sound through another channel. This should then give some extra options in editing with some added voice-over or music where needed. If I choose to use a microlight, then I'll probably do something similar.

I notice that the police (rick Bravo's team) use the on-camera mic + fur sock for some flight shoots:

http://home.mindspring.com/~ricks-pics/

Jimmy McKenzie
April 25th, 2005, 06:58 AM
Mic attenuated will likely be the best setting. Since you have multiple XLR inputs, you could use 2 lav mics ... one at the mic for Tx and a second inside the earmuff for Rx.

You could also use a frequency scanner and use the headphone out with a 1/8 mini to XLR adapter. That would give you the tower dialogue. Somewhere between 122.000 and 128.000. You likely have the frequency info already. 2 scanners perhaps? Best to test that setup on the ground with engines off and monitor the feed at the cam with your editing headphones on. Definately you'll need to ride the levels of each channel independently.

The ambient is critical to a polished final edit. The wide stereo omni pattern of the onboard mic is well suited to this.

Mike Benjamin
April 25th, 2005, 09:27 AM
Thanks Jimmy, I think you've answered it for me. Well done...

Mike