Audio Situation at DVinfo.net

Matt McLain · April 19th, 2004, 12:21 PM

We have a pretty large dialogue scene that we need to record for a short film that happens to take place on bus. We've done a bit of testing and we got lots of bus noise and little less dialogue. We're using an audio technica AT835b, core sound's denecke AD-20, and the IRIVER HP 120. Does anyone have any suggestions on what to do to try and cut out some of the surrounding bus noise and focus more on the dialogue? We'd like to avoid ADR as much as possible.

Thanks.

Mike Cavanaugh · April 19th, 2004, 12:33 PM

If you can, record the dialog on a stationary (quiet) bus. You can rock the bus from outside to simulate movement, and have the actors react to the movement. After that, go for the bus ride and record ambient audio and some of your cutaways of the actors looking out the window etc. Combine the two in post.

Jay Massengill · April 19th, 2004, 04:24 PM

If you have to have the bus actually moving on the road at all times for your visuals, then you'll probably have to go to lavs on the actors to get better isolation.
I'm assuming you miced as close as possible with the AT835b the first time(?) If not, you may want to try going closer, but you'll need to be even more careful about keeping the actors in the pattern. You might have to go with a wider pattern, more accurate mic to get close for isolation but not get out of the sweet spot so easily.
If you go with lavs, you'll still want to record with the shotgun or other mic to fill out the sound. This may require an additional recorder in order to keep all tracks separate. Or you can CAREFULLY use a mixer to make modest combinations of tracks.
Lastly, have you experimented with EQ to reduce the influence of the ambient bus noises versus the dialog?

Matt McLain · April 20th, 2004, 08:53 AM

Jay,

I have experimented with the EQ a little, and it does help. I also messed around with a noise reduction plugin for Soundforge, and that helped a lot, but it left the audio feeling kinda "empty" to me. We do have a pair of lavs, not sure what brand, so we'll probably go ahead and do what you suggested and record with those and the shotgun.

One question though, when you mention that I'd need to "fill out the sound" with the shotgun, does that mean that I'd have to mix both the sound from the shotgun and the lav sound in post? I'm new to this stuff (obviously), but it seems like that would give me a weird echo-like effect or something.

Thanks for your help.

Jay Massengill · April 20th, 2004, 09:39 AM

When mixing in a shotgun with a lav to fill out the sound, you must be very careful. First, you should stick with the 3 to 1 rule regarding the relative distance between mics and the subject.
If the lav on the subject is 1 foot from their mouth, then other mics should be at least 3 feet away to reduce phasing when the two signals are mixed.
(This is also true if you have two people wearing lavs and they are very close to each other. If they must be closer than 3 to 1, then you will have to either checkerboard edit or use extensive mixing in post to reduce the phasing.)
Second, you'll only be mixing in a small percentage of the ambient mic. It's safest to do this in post only, but that requires more tracks during recording in order to keep all mics separate.
You can do this mixing when recording to only two tracks, but you can't undo it if you get the mix wrong.
Experiment with the lavs you have. Depending on their pattern, response, and how you hide them, you may not need to fill out their sound.
You should also record several minutes of general bus ambience with the actors silent. Use this to polish up any rough spots during editing.
Lastly, work with the actors to minimize stepping on each other's lines. If both are talking simultaneously, that greatly limits your editing freedom. You must strike a balance between emotion and pace of delivery without having every exchange bridged by dialog from two people.

Marco Leavitt · April 20th, 2004, 11:14 AM

I have no suggestions other than to use lavs, which you're already hearing. I am curious -- how are you monitoring the levels on the Iriver? I thought that thing didn't have a meter. A lot of people (well, me) would love to hear about your experience using it if you wanted start another thread.

Matt McLain · April 20th, 2004, 01:06 PM

Well..... to answer your question about monitoring the levels... You're right. The IRIVER has no level meter, so we're pretty much just guessing all the time, which isn't working out too well. We really just started working on this short, and we're all pretty new to this. There's been a lot of testing, which is giving me a better idea of where to put the recording levels, but its nowhere near perfect. But the quality of the sound (to my untrained ear) is great with Iriver. The stuff we recorded in fairly controlled areas (quiet apartments... etc.) sounded pretty good. We used to record directly into our canon xl1, and compared to that sound, the Iriver is a miracle.

Matt McLain · April 20th, 2004, 01:10 PM

Oh... and we're broke, which explains why we haven't just gone out and bought a seperate meter. I've been looking at the Beachtek SVU 1, and that seems like a great meter for a great price. But when I say broke, I mean broke.

Marco Leavitt · April 20th, 2004, 01:23 PM

Just a suggestion, but you might try a separate meter like the one made by Sign Video. It’s like $100. I was thinking about a way to do this the other day, and I’ll bet you could use the CD from Jay Rose’s book on audio to calibrate the meter. There’s a track on there that will give you a 20 khz tone at 0 db. It’s what I used to calibrate the meter with my minidisc. Just hook the IRiver up to a CD player’s line out, and record about 30 seconds worth of sound. Then hook the meter to the headphone out of the IRiver, making sure that’s it’s turned all the way up -- assuming the headphone jack doesn’t distort at that level. If it does you’ll have to use a lower level, but make sure you memorize it, because whenever you use the meter the headphone output on the IRiver will have to be set at the same volume. Anyway, play back the track on the IRiver and turn the screws on the side of the meter to calibrate it so that the peak is at 0 db. This isn’t the most accurate way to monitor your levels, but it would have to beat guessing. As I said, I use it with my minidisc and so far it’s worked great. You didn’t ask for advice, but I thought this might be helpful. I’m also really curious to know if someone can get this to work, because the lack of a meter on the IRiver is a real bummer.

Marco Leavitt · April 20th, 2004, 01:24 PM

Sorry, didn't see your other post.

Matt McLain · April 20th, 2004, 01:31 PM

Thanks a lot for the advice Marco, and as soon as we can get a little extra cash together, (payday is coming up) I'll try out your suggestion.

Bryan Beasleigh · April 20th, 2004, 02:22 PM

<<<-- Originally posted by Marco Leavitt : Just a suggestion, but you might try a separate meter like the one made by Sign Video. It’s like $100. I was thinking about a way to do this the other day, and I’ll bet you could use the CD from Jay Rose’s book on audio to calibrate the meter. There’s a track on there that will give you a 20 khz tone at 0 db. >>>

You'd never hear a 20khz tone, the standard is a 1k. It may well have been recorded at 0 db but the only way you'd know that the output was at 0db was if you had a meter on it. I think Jay wanted us to hear the difference between -20, -12 and 0db.

I have the 1 k 0db test tone on my sound devices mix pre and 302, it makes setup easy, but there is no way to accrately reproduce it to that level from a recording without a meter.

Marco Leavitt · April 20th, 2004, 02:47 PM

Must have been a 1k tone then (track 14 I think?). I can't check, because I lent out my book. Apologies. I noticed that when I played the track from the line out on the CD player into the line in on my minidisc, with the gain set all the way up to 30, the level came to exactly the last line on the meter. Since the IRiver, like the minidisc and the CD player is consumer equipment, I figured that signal might be a good clue for where the IRiver would clip, assuming it has a line in. As I said, I'd be interested to know if anyone can get a cheap, external meter to work with the IRiver, and I've been pondering how it could be done. Sorry to hijack your post Matt. All you ever asked about was background noise. :)

April 19th, 2004, 12:21 PM	#1
Matt McLain Regular Crew Join Date: Feb 2004 Location: bloomington, il Posts: 40	Audio Situation We have a pretty large dialogue scene that we need to record for a short film that happens to take place on bus. We've done a bit of testing and we got lots of bus noise and little less dialogue. We're using an audio technica AT835b, core sound's denecke AD-20, and the IRIVER HP 120. Does anyone have any suggestions on what to do to try and cut out some of the surrounding bus noise and focus more on the dialogue? We'd like to avoid ADR as much as possible. Thanks.

April 19th, 2004, 12:33 PM	#2
Mike Cavanaugh Major Player Join Date: Dec 2003 Location: Albany NY Posts: 311	If you can, record the dialog on a stationary (quiet) bus. You can rock the bus from outside to simulate movement, and have the actors react to the movement. After that, go for the bus ride and record ambient audio and some of your cutaways of the actors looking out the window etc. Combine the two in post.

April 19th, 2004, 04:24 PM	#3
Jay Massengill Trustee Join Date: Jul 2003 Location: Burlington Posts: 1,976	If you have to have the bus actually moving on the road at all times for your visuals, then you'll probably have to go to lavs on the actors to get better isolation. I'm assuming you miced as close as possible with the AT835b the first time(?) If not, you may want to try going closer, but you'll need to be even more careful about keeping the actors in the pattern. You might have to go with a wider pattern, more accurate mic to get close for isolation but not get out of the sweet spot so easily. If you go with lavs, you'll still want to record with the shotgun or other mic to fill out the sound. This may require an additional recorder in order to keep all tracks separate. Or you can CAREFULLY use a mixer to make modest combinations of tracks. Lastly, have you experimented with EQ to reduce the influence of the ambient bus noises versus the dialog?

April 20th, 2004, 08:53 AM	#4
Matt McLain Regular Crew Join Date: Feb 2004 Location: bloomington, il Posts: 40	Jay, I have experimented with the EQ a little, and it does help. I also messed around with a noise reduction plugin for Soundforge, and that helped a lot, but it left the audio feeling kinda "empty" to me. We do have a pair of lavs, not sure what brand, so we'll probably go ahead and do what you suggested and record with those and the shotgun. One question though, when you mention that I'd need to "fill out the sound" with the shotgun, does that mean that I'd have to mix both the sound from the shotgun and the lav sound in post? I'm new to this stuff (obviously), but it seems like that would give me a weird echo-like effect or something. Thanks for your help.

April 20th, 2004, 09:39 AM	#5
Jay Massengill Trustee Join Date: Jul 2003 Location: Burlington Posts: 1,976	When mixing in a shotgun with a lav to fill out the sound, you must be very careful. First, you should stick with the 3 to 1 rule regarding the relative distance between mics and the subject. If the lav on the subject is 1 foot from their mouth, then other mics should be at least 3 feet away to reduce phasing when the two signals are mixed. (This is also true if you have two people wearing lavs and they are very close to each other. If they must be closer than 3 to 1, then you will have to either checkerboard edit or use extensive mixing in post to reduce the phasing.) Second, you'll only be mixing in a small percentage of the ambient mic. It's safest to do this in post only, but that requires more tracks during recording in order to keep all mics separate. You can do this mixing when recording to only two tracks, but you can't undo it if you get the mix wrong. Experiment with the lavs you have. Depending on their pattern, response, and how you hide them, you may not need to fill out their sound. You should also record several minutes of general bus ambience with the actors silent. Use this to polish up any rough spots during editing. Lastly, work with the actors to minimize stepping on each other's lines. If both are talking simultaneously, that greatly limits your editing freedom. You must strike a balance between emotion and pace of delivery without having every exchange bridged by dialog from two people.

April 20th, 2004, 11:14 AM	#6
Marco Leavitt Inner Circle Join Date: Jul 2002 Location: Albany, NY 12210 Posts: 2,652	I have no suggestions other than to use lavs, which you're already hearing. I am curious -- how are you monitoring the levels on the Iriver? I thought that thing didn't have a meter. A lot of people (well, me) would love to hear about your experience using it if you wanted start another thread.

April 20th, 2004, 01:06 PM	#7
Matt McLain Regular Crew Join Date: Feb 2004 Location: bloomington, il Posts: 40	Well..... to answer your question about monitoring the levels... You're right. The IRIVER has no level meter, so we're pretty much just guessing all the time, which isn't working out too well. We really just started working on this short, and we're all pretty new to this. There's been a lot of testing, which is giving me a better idea of where to put the recording levels, but its nowhere near perfect. But the quality of the sound (to my untrained ear) is great with Iriver. The stuff we recorded in fairly controlled areas (quiet apartments... etc.) sounded pretty good. We used to record directly into our canon xl1, and compared to that sound, the Iriver is a miracle.

April 20th, 2004, 01:10 PM	#8
Matt McLain Regular Crew Join Date: Feb 2004 Location: bloomington, il Posts: 40	Oh... and we're broke, which explains why we haven't just gone out and bought a seperate meter. I've been looking at the Beachtek SVU 1, and that seems like a great meter for a great price. But when I say broke, I mean broke.

April 20th, 2004, 01:23 PM	#9
Marco Leavitt Inner Circle Join Date: Jul 2002 Location: Albany, NY 12210 Posts: 2,652	Just a suggestion, but you might try a separate meter like the one made by Sign Video. It’s like $100. I was thinking about a way to do this the other day, and I’ll bet you could use the CD from Jay Rose’s book on audio to calibrate the meter. There’s a track on there that will give you a 20 khz tone at 0 db. It’s what I used to calibrate the meter with my minidisc. Just hook the IRiver up to a CD player’s line out, and record about 30 seconds worth of sound. Then hook the meter to the headphone out of the IRiver, making sure that’s it’s turned all the way up -- assuming the headphone jack doesn’t distort at that level. If it does you’ll have to use a lower level, but make sure you memorize it, because whenever you use the meter the headphone output on the IRiver will have to be set at the same volume. Anyway, play back the track on the IRiver and turn the screws on the side of the meter to calibrate it so that the peak is at 0 db. This isn’t the most accurate way to monitor your levels, but it would have to beat guessing. As I said, I use it with my minidisc and so far it’s worked great. You didn’t ask for advice, but I thought this might be helpful. I’m also really curious to know if someone can get this to work, because the lack of a meter on the IRiver is a real bummer.

April 20th, 2004, 01:24 PM	#10
Marco Leavitt Inner Circle Join Date: Jul 2002 Location: Albany, NY 12210 Posts: 2,652	Sorry, didn't see your other post.

April 20th, 2004, 01:31 PM	#11
Matt McLain Regular Crew Join Date: Feb 2004 Location: bloomington, il Posts: 40	Thanks a lot for the advice Marco, and as soon as we can get a little extra cash together, (payday is coming up) I'll try out your suggestion.

April 20th, 2004, 02:22 PM	#12
Bryan Beasleigh Trustee Join Date: May 2002 Location: Barrie, Ontario, Canada Posts: 1,922	<<<-- Originally posted by Marco Leavitt : Just a suggestion, but you might try a separate meter like the one made by Sign Video. It’s like $100. I was thinking about a way to do this the other day, and I’ll bet you could use the CD from Jay Rose’s book on audio to calibrate the meter. There’s a track on there that will give you a 20 khz tone at 0 db. >>> You'd never hear a 20khz tone, the standard is a 1k. It may well have been recorded at 0 db but the only way you'd know that the output was at 0db was if you had a meter on it. I think Jay wanted us to hear the difference between -20, -12 and 0db. I have the 1 k 0db test tone on my sound devices mix pre and 302, it makes setup easy, but there is no way to accrately reproduce it to that level from a recording without a meter.

April 20th, 2004, 02:47 PM	#13
Marco Leavitt Inner Circle Join Date: Jul 2002 Location: Albany, NY 12210 Posts: 2,652	Must have been a 1k tone then (track 14 I think?). I can't check, because I lent out my book. Apologies. I noticed that when I played the track from the line out on the CD player into the line in on my minidisc, with the gain set all the way up to 30, the level came to exactly the last line on the meter. Since the IRiver, like the minidisc and the CD player is consumer equipment, I figured that signal might be a good clue for where the IRiver would clip, assuming it has a line in. As I said, I'd be interested to know if anyone can get a cheap, external meter to work with the IRiver, and I've been pondering how it could be done. Sorry to hijack your post Matt. All you ever asked about was background noise. :)