Removing "Echo" when Using Camera + External Audio Recorder

DrewG

DrewG

Pre-takeoff checklist
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DrewG
This is an extremely niche problem, but I can't find anything online that addresses this specific issue and I figured we have a few video "pros" on the board that might be able to help or share their processes.

On the occasions that I record my flights (or flights with others, to share their experience with them), I use a 3-camera setup and record all cockpit/ATC audio through an external Sony recorder.

Of course, the main audio I use when producing a video is from the Sony voice recorder, but I also like to include the audio track from one of the in-cockpit cameras turned way down for some ambient engine noise, tire squeaks, etc.

The issue I have is that in low-RPM situations - such as landings, ground operations etc. - I get an "echo" of what's being said in the cockpit (and captured on the Sony voice recorder main track) that was picked up from the in-cockpit camera and I can't figure out how to eliminate it without turning off that track completely - thus losing the ambient engine noise. It is nigh impossible to get the audio tracks between my recorder and in-cockpit cameras to sync up perfectly, so there is ALWAYS an echo when on the ground between tracks, no matter how far I turn down the camera audio without muting it completely.

What remedies do you use to keep the ambient noise and remove the voice echoes? Just replace the areas of "echo" with a looped clip from similar low-RPM ops where no one is actually talking? Or is there some audio editing trick within the track I can employ? This isn't a major problem, but an annoyance I'm hoping to see how others handle in their editing of videos when including ambient engine noise.

For reference, I use CyberLink PowerDirector 365 for my editing.
 
DrewG said:
The issue I have is that in low-RPM situations - such as landings, ground operations etc. - I get an "echo" of what's being said in the cockpit (and captured on the Sony voice recorder main track) that was picked up from the in-cockpit camera and I can't figure out how to eliminate it without turning off that track completely - thus losing the ambient engine noise.
Click to expand...

Three ways off the top of my head:

1) The ambient noise is overrated. Turn it off.
2) Put another external recorded somewhere further away to capture ambient, but not your voice.
3) Dub other ambient noise from elsewhere in the clip during the part when you are talking. No one other than you will notice.

I use 1 almost exclusively, but sometimes 3. I challenge anyone to find the two occasions in this video where I use number 3. One is kind of obvious, the second would only be found by dumb luck.

 
Are you syncing the audio "1,2,3 clap!" ?
sounds like it is just misaligned.

I turn on all recording devices and do the 321 clap method or just yell clear prop then Premier has a tool that will auto align all tracks based on that sound event.
 
It seems too low-budget to work but I actually like the "stick a mic in your headset earcup" method. Then you get both radio audio and ambient noise on one track.
 
dmspilot said:
It seems too low-budget to work but I actually like the "stick a mic in your headset earcup" method. Then you get both radio audio and ambient noise on one track.
Click to expand...
What mike are you using for that?
 
SixPapaCharlie said:
Are you syncing the audio "1,2,3 clap!" ?
sounds like it is just misaligned.

I turn on all recording devices and do the 321 clap method or just yell clear prop then Premier has a tool that will auto align all tracks based on that sound event.
Click to expand...

I do use this method, but the PowerDirector multi-cam editor is absolute trash at picking this up and aligning the sound, so I always end up having to doing it manually. Furthermore, when using the multi-cam edit feature in PD, only one audio source is able to be selected for the ENTIRE edit (which is the voice recorder). So, when I finish my multi-cam edit, it automatically gets plugged into a track, and then I have to go back and sync the "ambient" sound on another track below the finished multi-cam edit's track. I'm sure there's a way to mitigate this, but I edit so infrequently that I don't really know how.

I'd switch to the Adobe products, but this PowerDirector is kind of the "devil I know" - or at least I'm acquainted with. I feel like I'm the only one that uses it! I haven't even bothered to try color correction or white balance, either.

I already wear hearing aids, so using the "mic in the headset" trick would probably prove a bit uncomforatble.
 
No expert but I have done the SONY recorder thing and have gotten the "500...500" echo. You wind up finding a great spot to sync the tracks and do a perfect job by aligning the audio wave forms, only to have the echo reappear later in the track.

What's actually happening is that the SONY is recording at a very slightly different speed than the camera. So no mater how well you sync at Point A, they ultimately unsync. The ultimate answer to to change the speed of the audio file which comes from the SONY (if you software is capable of it). Sync at Point A and adjust the speed so it's still synced at Points B later in the track.
 
midlifeflyer said:
No expert but I have done the SONY recorder thing and have gotten the "500...500" echo. You wind up finding a great spot to sync the tracks and do a perfect job by aligning the audio wave forms, only to have the echo reappear later in the track.

What's actually happening is that the SONY is recording at a very slightly different speed than the camera. So no mater how well you sync at Point A, they ultimately unsync. The ultimate answer to to change the speed of the audio file which comes from the SONY (if you software is capable of it). Sync at Point A and adjust the speed so it's still synced at Points B later in the track.
Click to expand...

Now that you mention this, it is EXACTLY my problem. I hadn't even thought about it until you stated it, but every single time I do a bang-up job of syncing, I end up scratching my head at how the audio is perfect at Point A and got out-of-sync at Point B.

I know there's a whole audio editing plug-in component with my software, so I'll check this out. What percentage up or down do you find you generally need to tweak the speed?
 
In the broadcast world they use time code to,keep things in sync - but even at that you can find product that makes it onto cable/broadcast/pro-stuff where the audio is out of synch with the lip movement. It's annoying for me to watch.

Unless the recorders have an option to sync against each other you're likely to have an issue. If you can add a cabin mic to the main recorder, you'd get everything on one device and have a pretty good chance to keep the channels synced. Or use a video editing package that allows you to edit one audio channel separately from the rest (and separately from the video).
 
SixPapaCharlie said:
Are you syncing the audio "1,2,3 clap!" ?
sounds like it is just misaligned.

I turn on all recording devices and do the 321 clap method or just yell clear prop then Premier has a tool that will auto align all tracks based on that sound event.
Click to expand...

This is actually a pretty savvy move as long as the time doesn't 'slip' during the recording. Not all device record and playback in perfect time...

Your issue is basically delay in the processing of the devices recording and editing the video and audio...using delay on the audio can fix it unless you are ahead of the video track...then 6PC's clap reference is an Easy New York Teenage™ method way of audio video alignment.
 
DrewG said:
I do use this method, but the PowerDirector multi-cam editor is absolute trash at picking this up and aligning the sound, so I always end up having to doing it manually. Furthermore, when using the multi-cam edit feature in PD, only one audio source is able to be selected for the ENTIRE edit (which is the voice recorder). So, when I finish my multi-cam edit, it automatically gets plugged into a track, and then I have to go back and sync the "ambient" sound on another track below the finished multi-cam edit's track. I'm sure there's a way to mitigate this, but I edit so infrequently that I don't really know how.

I'd switch to the Adobe products, but this PowerDirector is kind of the "devil I know" - or at least I'm acquainted with. I feel like I'm the only one that uses it! I haven't even bothered to try color correction or white balance, either.

I already wear hearing aids, so using the "mic in the headset" trick would probably prove a bit uncomforatble.
Click to expand...

I used power director for years and was in the same situation and finally I just dove into Adobe. I can't stand that I have to rent it monthly but once you get used to it it really does speed up the editing process a lot
 
I appreciate everyone's input here and I'll tinker around with your ideas/suggestions. If all else fails, I may just go with the very first suggestion of removing the ambient sound altogether!

SixPapaCharlie said:
I used power director for years and was in the same situation and finally I just dove into Adobe. I can't stand that I have to rent it monthly but once you get used to it it really does speed up the editing process a lot
Click to expand...

To take a theme/voice from some of your recent YT videos, "have I got neeewwws for you!" PowerDirector also moved to a "monthly rent" setup - but I paid for a year up front when I upgraded versions. Maybe I'll dive into Adobe (and their monthly payments) if PD keeps frustrating me the way it does. I keep thinking that I'm actually doing a good job with it, then I happen upon a video tutorial on an Adobe product that helps skip about 3 steps from what's required in PD for any particular task.
 
DrewG said:
Now that you mention this, it is EXACTLY my problem. I hadn't even thought about it until you stated it, but every single time I do a bang-up job of syncing, I end up scratching my head at how the audio is perfect at Point A and got out-of-sync at Point B.

I know there's a whole audio editing plug-in component with my software, so I'll check this out. What percentage up or down do you find you generally need to tweak the speed?
Click to expand...
I'm not going to be able to check until sometime tomorrow afternoon. But it was tiny. And mine might not help except as a very general guide since the camera I used wasn't a GoPro so it might be different than yours.
 
DrewG said:
If all else fails, I may just go with the very first suggestion of removing the ambient sound altogether!
Click to expand...
Personally, I like the ambient sound. I think the sound of the engine (lowered) makes a good background and is more interesting.
 
midlifeflyer said:
I'm not going to be able to check until sometime tomorrow afternoon. But it was tiny. And mine might not help except as a very general guide since the camera I used wasn't a GoPro so it might be different than yours.
Click to expand...

Thank you! I'll appreciate any starting point. My other cameras are of non-GoPro branding, so I'll have to tinker with it regardless, I presume. I also agree with you on the ambient sound; it certainly adds a little character to the video. Silence is too stark for me, so omitting the ambient noise would certainly be a last resort.
 
I'll tell you another secret. I have audio recordings of my plane in cruise on take off on landing both from the inside and the outside and I just reuse those audio samples.

Taxi.mp3
runup.mp3
GrummanThrottleupInside.mp3
Etc...
 
I prefer to have at least some engine noise, too. I've been using Videopad editor, which is free unless you want to unlock some of the advanced features I've never needed. You can overlay multiple audio tracks and fade them in and out. External cameras mostly give you wind noise once you're moving. I typically start with the ambient louder, then fade it back after takeoff to a background level when the music starts. I got a little more creative with this one, though:

 
SixPapaCharlie said:
I'll tell you another secret. I have audio recordings of my plane in cruise on take off on landing both from the inside and the outside and I just reuse those audio samples.

Taxi.mp3
runup.mp3
GrummanThrottleupInside.mp3
Etc...
Click to expand...
I though you made those zoom zoom noises with your mouth!
 
midlifeflyer said:
What's actually happening is that the SONY is recording at a very slightly different speed than the camera.
Click to expand...
That may not be what's happening. I've had to shoot video of safety meetings at work as well as produce in-house safety videos and I will usually use multiple cameras and a separate audio recorder. What I've found is the audio coming from the audio recorder is dead nuts accurate. But one or more of the video feeds was shot using a variable frame rate setting. Getting the audio to sync is just about impossible if the video (and thus any audio recorded with it) was shot using a variable frame rate.

The solution for previously shot video is to run the raw video through software that will convert it to a fixed frame rate.
The solution for future video shoots is the make sure to set all cameras to shoot at the same fixed frame rate if possible. If that's not possible, run the raw video through a frame rate converter as the first step in your editing process.
 
DrewG said:
Thank you! I'll appreciate any starting point. My other cameras are of non-GoPro branding, so I'll have to tinker with it regardless, I presume. I also agree with you on the ambient sound; it certainly adds a little character to the video. Silence is too stark for me, so omitting the ambient noise would certainly be a last resort.
Click to expand...
The factor that worked for me (but it was only a 3-1/2 minute video) was 0.997720.
 
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Juliet Hotel said:
That may not be what's happening. I've had to shoot video of safety meetings at work as well as produce in-house safety videos and I will usually use multiple cameras and a separate audio recorder. What I've found is the audio coming from the audio recorder is dead nuts accurate. But one or more of the video feeds was shot using a variable frame rate setting.
Click to expand...
Like I said, I'm no expert. I just know what received as a recommendation and it worked for me on my relatively short videos.

Update... But I will definitely try it next time. I downloaded Handbrake and indeed the video was variable rate! Thank you.
 
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