synchronizing beds with a live recording HALP
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- audio school
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synchronizing beds with a live recording HALP
hello tape op'ers. i've run into a tricky situation and have spent too long trying to do it only on my own.
so i have this musical project called 'livestalk and the bodies'. for the performance, i pre-record acoustic guitar and 4-5 part harmonies and play them thru an mp3 player (guitar L and harms R) while i play drums and sing live.
someone took a professional video of my last set, but the backing tracks are super quiet in the camera's mic. i asked the camera person if they could send me just the audio wav file so i could line it up with my bed tracks at home.
all the songs are one giant track, and each have count in's (that are also audible in the camera mic), so i thought this would be pretty easy to line up.
my problem comes in when i line up any one of the count in sounds, the beds seem to be moving faster than on the camera mics (but the pitch is the same) the result is, it sounds lined up for about thirty seconds and then the beds start to move faster.
originally i thought i might just be mis-alligning them up but i feel like there's something more to this, cos if they're theoretically the same speed, i should be able to set the beds ahead of the beat, and they should be ahead of the beat the whole way thru. i've tested this by putting it intentionally behind, and eventually it lines up and then starts going ahead again.
is it at all possible that when i exported the files it time stretched it? if so how do i prevent this? how do i figure out how much i stretched it so i can alter the beds to line em up
ALTERNATIVELY: if the case is i'm really just not lining it up properly, does anyone have any tools or suggestions to help with a problem like this???
thank yew
so i have this musical project called 'livestalk and the bodies'. for the performance, i pre-record acoustic guitar and 4-5 part harmonies and play them thru an mp3 player (guitar L and harms R) while i play drums and sing live.
someone took a professional video of my last set, but the backing tracks are super quiet in the camera's mic. i asked the camera person if they could send me just the audio wav file so i could line it up with my bed tracks at home.
all the songs are one giant track, and each have count in's (that are also audible in the camera mic), so i thought this would be pretty easy to line up.
my problem comes in when i line up any one of the count in sounds, the beds seem to be moving faster than on the camera mics (but the pitch is the same) the result is, it sounds lined up for about thirty seconds and then the beds start to move faster.
originally i thought i might just be mis-alligning them up but i feel like there's something more to this, cos if they're theoretically the same speed, i should be able to set the beds ahead of the beat, and they should be ahead of the beat the whole way thru. i've tested this by putting it intentionally behind, and eventually it lines up and then starts going ahead again.
is it at all possible that when i exported the files it time stretched it? if so how do i prevent this? how do i figure out how much i stretched it so i can alter the beds to line em up
ALTERNATIVELY: if the case is i'm really just not lining it up properly, does anyone have any tools or suggestions to help with a problem like this???
thank yew
My guess is there is some funky sample rate conversion or clocking going on somewhere between your original export (the file you used live), your MP3 player, or the camera audio.
Just for fun you might play back the MP3 player into your computer and record THAT version of your bed and see if the time on that is similar. Maybe not "ideal" but I'm guessing the offender is either your MP3 player or the camera.
Just for fun you might play back the MP3 player into your computer and record THAT version of your bed and see if the time on that is similar. Maybe not "ideal" but I'm guessing the offender is either your MP3 player or the camera.
Some audio software allows you to Tempo correct, can you time the beds and then tempo correct the backing tracks to match? Lime I can tell my software make this track 455.87 seconds long, type deal.
The previous statement is from a guy who records his own, and other projects for fun. No money is made.
- Gregg Juke
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Yeah, something is definitely going on. Possibilities? Video audio is usually at 48, are you working with audio at 44.1? Also, the MP3 tracks-- Are they actually MP3's? MP3 files and .wav files of the same tracks will not line-up (perfectly and permanently), regardless of program material or if they are at the same pitch. Add to that the fact that there is often drift between camera audio and "wild-tracked" (un-synced) on-set audio, and it looks like you will at least need to cut the tracks at a few points and make a few adjustments to re-align at minimum. Hopefully not too much work in too many places...
GJ
GJ
Gregg Juke
Nocturnal Productions Music Group
Drum! Magazine Contributor
http://MightyNoStars.com
"He's about to learn the most important lesson in the music business-- 'Never trust people in the music business.' "
Nocturnal Productions Music Group
Drum! Magazine Contributor
http://MightyNoStars.com
"He's about to learn the most important lesson in the music business-- 'Never trust people in the music business.' "
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Welcome to the wonderful World of unsynced audio.
1. The mp3 player played at a slightly different rate of speed than the video camera recording the show, which is playing back the audio at a different rate of speed than whatever computer you are using to edit your music to the picture audio.
This is how you can fix this, at least try to fix this:
First, write down the sample rate of each of the three devices. Do they match?
Start a brand new project, and make the sample rate match the VIDEO track. It will hopefully be 48kHz 16 bit or 24 bit.
Import the other audio, both the one from the mp3 player, and your audio from your other DAW project. Make SURE this audio is CONVERTED and COPIED into your project into the correct 48kHz sample rate.
Even after you do this, there will be some difference, however it should be a lot less.
I think at some point in your cavorting around, one or more of the audio files got screwed up.
Let us know if this improves the problem. It won't make it 100% disappear, but it should eliminate one possibility.
Cheers
1. The mp3 player played at a slightly different rate of speed than the video camera recording the show, which is playing back the audio at a different rate of speed than whatever computer you are using to edit your music to the picture audio.
This is how you can fix this, at least try to fix this:
First, write down the sample rate of each of the three devices. Do they match?
Start a brand new project, and make the sample rate match the VIDEO track. It will hopefully be 48kHz 16 bit or 24 bit.
Import the other audio, both the one from the mp3 player, and your audio from your other DAW project. Make SURE this audio is CONVERTED and COPIED into your project into the correct 48kHz sample rate.
Even after you do this, there will be some difference, however it should be a lot less.
I think at some point in your cavorting around, one or more of the audio files got screwed up.
Let us know if this improves the problem. It won't make it 100% disappear, but it should eliminate one possibility.
Cheers
Howling at the neighbors. Hoping they have more mic cables.
Just had a wonderful flashback to my Blueman days. Used to deal with this sort of thing CONSTANTLY. All of the aforementioned things could possibly be true, but what it sounds like to me is pull up/down.
Short story is that video don't care about no timing issues when you convert frame rates, so you get all kinds of nightmare scenarios (harsh? maybe). The end result is audio that seems to be the correct pitch but drifts over time. PT has pull up and down options to compensate in the Import Audio window, source sample rate dropdown. Try 'em out and see which one matches.
I personally never had drift issues with mp3 conversion. Protools used to add a bit of dead air at the end when you bounced to mp3, dunno if it still does.
Short story is that video don't care about no timing issues when you convert frame rates, so you get all kinds of nightmare scenarios (harsh? maybe). The end result is audio that seems to be the correct pitch but drifts over time. PT has pull up and down options to compensate in the Import Audio window, source sample rate dropdown. Try 'em out and see which one matches.
I personally never had drift issues with mp3 conversion. Protools used to add a bit of dead air at the end when you bounced to mp3, dunno if it still does.
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- zen recordist
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