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Old August 2nd, 2007, 05:20 AM   #16
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Originally Posted by Mike Costantini View Post
Hmm... Well what other choice would I have? The L&R outs from the mixer go into a direct box and come out as one XLR that plugs into the XLR input on my camera. So when I capture the tape, I have a video and audio stream (consisting of the guitar, mic, and tracks). Is there another way to do it? We've always just gotten the audio the way we want it to sound, then just record; didn't know there was another way? In addition, the guitar player won't want to play with a dry sounding guitar (no reverb), makes it difficult..
Is he unable to play the music without hearing the reverb??? If that's the case you have no choice but to lose the speakers and get him to wear headphones or in-ear monitors. If he can play it but just is worried it won't sound right in the video, convince him that he's not doing a live performance but making a recording and different rules apply - the material he's recording is only the raw material for the final soundtrack which is actually going to be assembled in post production. Either that or get another mixer as well as the one you have or upgrade your current mixer to one with more aux sends and more flexible routing options.

Another option occurred to me just now. You said you were taking the main outs to a direct box and then to an xlr input to the camera. That sounds like you're mixing them to mono and only using one channel of audio in the camera. Is that the case or do you have a 2-channel DI box, or do you have two direct boxes? If you're only using one channel in the camera, take the mic off the mixer completely and send it directly into the second camera audio channel, doing the mixdown with the music tracks in post. The guitar and backing tracks would still go to the mixer, monitors, and DI box just as they are now.
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Old August 2nd, 2007, 06:52 AM   #17
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Steve House is a saint. Very good work, Steve.

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Old August 2nd, 2007, 08:08 AM   #18
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Originally Posted by Mike Costantini View Post
...The problem I am having is that when I turn up the monitor volume from the mixer, it creates that waaaaooo feedback sound. How does one overcome this?
Anytime it's a live sound situation, the sound system needs to have the proper EQ curve for the space and mics.

In addition to the good advice you've received, the send to the speakers/amp should be routed through a graphic EQ. Play a strong signal of pink noise through the system and adjust the frequencies curve using a spectrum analyzer.

Or...gradually turn up the volume to the point of feedback and identify and reduce the offending frequencies.
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Old August 2nd, 2007, 08:30 AM   #19
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Simple, don't feed the mic to the PA.

This was outlined in great detail by Steve House's reply.

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Old August 2nd, 2007, 12:47 PM   #20
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Originally Posted by Steve House View Post
Is he unable to play the music without hearing the reverb??? If that's the case you have no choice but to lose the speakers and get him to wear headphones or in-ear monitors. If he can play it but just is worried it won't sound right in the video, convince him that he's not doing a live performance but making a recording and different rules apply - the material he's recording is only the raw material for the final soundtrack which is actually going to be assembled in post production.
Trust me, a stubborn old musician is set in his ways. He wants to hear the guitar with the effects as he plays as he has done forever =)

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Either that or get another mixer as well as the one you have or upgrade your current mixer to one with more aux sends and more flexible routing options.
I do have another mixer in a Yamaha recorder I've used before so that's a possibility....

Quote:
Another option occurred to me just now. You said you were taking the main outs to a direct box and then to an xlr input to the camera. That sounds like you're mixing them to mono and only using one channel of audio in the camera. Is that the case or do you have a 2-channel DI box, or do you have two direct boxes?
The direct box I'm using is this:
http://www.rolls.com/products/db25.php
It takes in two 1/4" inputs from the mixer and outputs one XLR which goes to my camera. Honestly I don't even know what the direct box is for, someone told me I need one, so I got it and it seems to work ok...

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If you're only using one channel in the camera, take the mic off the mixer completely and send it directly into the second camera audio channel, doing the mixdown with the music tracks in post. The guitar and backing tracks would still go to the mixer, monitors, and DI box just as they are now.
If I recall correctly, I tried to do something similar so I could have the guitar and music on two channels in case one was recorded too loud or too soft. From what I remember, when I tried to capture the tape to the computer, it only captured one channel of audio. Do I have to use the same camera I shot with to capture the tape (and both channels of audio)? What I do is shoot with my good camera and capture with an older Canon miniDV camcorder (to save as much heads use on the good cam)

I really appreciate all the replies here!!
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Old August 2nd, 2007, 01:15 PM   #21
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Originally Posted by Mike Costantini View Post
Trust me, a stubborn old musician is set in his ways. He wants to hear the guitar with the effects as he plays as he has done forever =)



I do have another mixer in a Yamaha recorder I've used before so that's a possibility....



The direct box I'm using is this:
http://www.rolls.com/products/db25.php
It takes in two 1/4" inputs from the mixer and outputs one XLR which goes to my camera. Honestly I don't even know what the direct box is for, someone told me I need one, so I got it and it seems to work ok...



If I recall correctly, I tried to do something similar so I could have the guitar and music on two channels in case one was recorded too loud or too soft. From what I remember, when I tried to capture the tape to the computer, it only captured one channel of audio. Do I have to use the same camera I shot with to capture the tape (and both channels of audio)? What I do is shoot with my good camera and capture with an older Canon miniDV camcorder (to save as much heads use on the good cam)

I really appreciate all the replies here!!
Yep, the DI box is a mono box. The two inputs are in parallel so you're mixing the L&R outputs of the mixer as they go into the box. Combining L&R by simply Y'ing them together (which is what that's doing, just not using a "Y" cable to do it) may or may not compromise your sound. So if the mixer is going to the DI and from there to the camera, you're only using one of the camera's two stereo tracks so far. Don't have a clue why you only got one audio channel when you captured a stereo recording before. That's not what's supposed to happen - you should have gotten a single stereo track with two channels and most editing software should let you then split them off into two mono tracks.

You said earlier that you were mixing the mic, the guitar, and a MIDI background track. The shotgun mic is obviously going to be mono but what are your signal sources for the guitar and the MIDI track? I assume you're getting the guitar as a mono signal off on its pickup, is that right. But what's the MIDI track coming from and is it mono or stereo?
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Old August 2nd, 2007, 01:24 PM   #22
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You said earlier that you were mixing the mic, the guitar, and a MIDI background track. The shotgun mic is obviously going to be mono but what are your signal sources for the guitar and the MIDI track? I assume you're getting the guitar as a mono signal off on its pickup, is that right. But what's the MIDI track coming from and is it mono or stereo?
The guitar signal goes into a PreSonus Bluetube (to give it some juice and warm it up) and then out to the mixer into channel 1. The MIC goes into the other channel of the Bluetube and then out to the mixer on Channel 2. The MIDI tracks are played from a MIDI player which we're taking the MONO output of straight into channel 3 on the mixer. It's been a long while since I tried using both channels on the camera to capture different audio so I'll give it a try, among your other suggestions, today.

Because of all these problems, I'm allowed to purchase another mixer - Do you have any recommendations on what I should get? The other mixer I mentioned I have is a Yamaha MD4S. Should I be using a different direct box, do I even need a direct box..... I'm not shooting hollywood epics here, just instructional DVDs =)

Last edited by Mike Costantini; August 2nd, 2007 at 02:02 PM.
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Old August 2nd, 2007, 03:07 PM   #23
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The guitar signal goes into a PreSonus Bluetube (to give it some juice and warm it up) and then out to the mixer into channel 1. The MIC goes into the other channel of the Bluetube and then out to the mixer on Channel 2. The MIDI tracks are played from a MIDI player which we're taking the MONO output of straight into channel 3 on the mixer. It's been a long while since I tried using both channels on the camera to capture different audio so I'll give it a try, among your other suggestions, today.

Because of all these problems, I'm allowed to purchase another mixer - Do you have any recommendations on what I should get? The other mixer I mentioned I have is a Yamaha MD4S. Should I be using a different direct box, do I even need a direct box..... I'm not shooting hollywood epics here, just instructional DVDs =)
Does your camera only have mic level inputs or can you send it line level?
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Old August 2nd, 2007, 03:09 PM   #24
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It's a Panasonic DVC-80, on each of the two inputs, there is a switch for mic or line level. I'm going to try plugging the mic directly into the camera from the Bluetube on Input 1 - So I don't destroy the camera, should I have that input on mic or line level?
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Old August 2nd, 2007, 04:01 PM   #25
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It's a Panasonic DVC-80, on each of the two inputs, there is a switch for mic or line level. I'm going to try plugging the mic directly into the camera from the Bluetube on Input 1 - So I don't destroy the camera, should I have that input on mic or line level?
Set both of your camera's XLR inputs to line level and forget the DI box (the DI box is to take line level, generally direct from a guitar or similar instrument, and drop it to mic level wihile matching impedance). Send the mic to the Blue on Ch1 and send Blue's Ch1 output direct to the camera on Input 1. Send the Guitar to the Blue on Ch 2 and Blue's Ch 2 out to a mixer line input. Send the mono MIDI playback to a second line input. Setup your reverb and monitoring as you like, monitors on the control room outs. You can use either mixer output channel to send to the camera since you're already in mono and the two should be identical. Convention would be to use the left so send the left main out to the camera input 2 through a TRS to XLR cable.

Try like heck to convince him headphones look cool and professional. Point out the Sirius radio commercials where all the talent is wearing cans. I have a copy of Roger McQuinn's (The Byrds, "Mr Tamborine Man") DVD "Guide To Home Recording Using a Computer," an instructional DVD not unlike what I'll wager you're shooting. And when McGuinn's playing and singing, guess what ... he's wearing headphones and singing into an on-camera studio vocal mic. Show your talent the video clip in this link, I think he'll agree it doesn't look at all silly or obtrusive

http://www.homespuntapes.com/prodpg/...1129&prodType=

The idea is to try to prevent bleed from the playback/monitoring speakers over into the same channel as the voice and you're still going to get that which could give you some headaches in post as you mix the two together. But at least this arrangement will kill the feedback.
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Old August 2nd, 2007, 08:08 PM   #26
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I did it! I was a little concerned because that NTG mic picks up quite a bit more than voice - it was picking up the guitar playing from the guitar itself. It sounded very strange to hear that in the headphones, but when I captured it and dropped it onto the timeline, duplicated the audio track, and then picked left channel only for one track, and right channel only for the other track, it sounded pretty good. I can always just cut the power to the mic altogether while the guitar and sequencer are playing at the same time, or I can cut it in the post production as well. But it seems to give everything a fuller sound as it picks up the sounds in the room such as the guitar and the monitor speaker playing the guitar and sequencer.. The NTG mic is superb! The audio from it is crystal clear, couldn't be happier to NOT be using that lavalier! One thing I noticed is that I have to bring the gain on the Bluetube almost all the way up to get a hot signal on that mic, before with the directbox, it didn't need that much juice. Are you positive the setting on the camera should be LINE instead of MIC? If you want I can post some audio samples from our test.

It would be great if I could have everything on a separate channel but I guess that isn't possible with only a left and right in the camera and on the tape..
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Old August 3rd, 2007, 04:58 AM   #27
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I did it! I was a little concerned because that NTG mic picks up quite a bit more than voice - it was picking up the guitar playing from the guitar itself. It sounded very strange to hear that in the headphones, but when I captured it and dropped it onto the timeline, duplicated the audio track, and then picked left channel only for one track, and right channel only for the other track, it sounded pretty good. I can always just cut the power to the mic altogether while the guitar and sequencer are playing at the same time, or I can cut it in the post production as well. But it seems to give everything a fuller sound as it picks up the sounds in the room such as the guitar and the monitor speaker playing the guitar and sequencer.. The NTG mic is superb! The audio from it is crystal clear, couldn't be happier to NOT be using that lavalier! One thing I noticed is that I have to bring the gain on the Bluetube almost all the way up to get a hot signal on that mic, before with the directbox, it didn't need that much juice. Are you positive the setting on the camera should be LINE instead of MIC? If you want I can post some audio samples from our test.

It would be great if I could have everything on a separate channel but I guess that isn't possible with only a left and right in the camera and on the tape..
Glad it's finally working for you. AFAIK your camera should be set on line levels, since that's what both the mic pre amplifier and the mixer are outputting. Just how hot are you trying to get it in the camera?

Which output connection are you using on the Blue for the mic channel? The XLR outpout is pro line level, +4dBu when the meter reads 0VU but the TRS output is -10dBv, a lot lower level! Your camera wants pro level line so be sure to use the XLR connector for the line for the mic channel from the preamp to the camera. When the 0VU lights are illuminated on the meters on both the Bluetube and the mixer you're getting +4dBu output, pro line level. The camera specs say its line input sensitivity is nominally 0dBu, which is normal for digital equipment. So if the 0VU lights are flickering on the Blue, you should be seeing the camera's meter somewhere around -12dB with normal speech. Also be sure you don't have the -20db pad on the Blue switched on in the mic channel.

I forget where you said you had the mic positioned. It should be above and to the front of the talent, directly above the line between his face and the lens, aimed at about a 45 degree downard angle towards his mouth. Get it as close to him as possible without intruding into frame. You might try a stage wedge on the floor in front of him instead of the PA speakers if he insists on no 'phones. Position the mic first for best voice quality, then put the wedge on the floor farther away from him so a line from the wedge to the mic would be at 90 degrees to the axis of the mic, that way it's in the maximum null of the mic pattern. While wearing phones to monitor, experiment moving the wedge back and forth until you find the spot of least pickup. That should help minimize the bleed from the monitors. There's no way you're going to eliminate it completely without getting him to wear cans. The place to clean up the bleed is in post - when he's playing, mute the track from the mic.
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Old August 3rd, 2007, 12:52 PM   #28
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I'm using the XLR connection on both ends from the bluetube to the camera. One thing I should note is that I didn't have a short cable for that connection so I'm using a pretty long one, probably 25 feet or so - Does the length of that cable matter much?

The mic is indeed positioned above and slightly in front of the subject's mouth, aimed down at the mouth and out of the picture frame.

I have that RAMSA speaker pointed at him about 10 feet or so in front of him.

Here's a few mp3 samples I made from the recording below. The first two are the same section on the timeline, I just muted each channel and encoded them separately. (I know the mix between the guitar and MIDI track is bad) The third one is both channels together with some talking and guitar, no sequencer:

Guitar & MIDI sequence channel

Mic channel

Talking & Guitar, both channels
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Old August 3rd, 2007, 02:37 PM   #29
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I'm using the XLR connection on both ends from the bluetube to the camera. One thing I should note is that I didn't have a short cable for that connection so I'm using a pretty long one, probably 25 feet or so - Does the length of that cable matter much?

The mic is indeed positioned above and slightly in front of the subject's mouth, aimed down at the mouth and out of the picture frame.

I have that RAMSA speaker pointed at him about 10 feet or so in front of him.

Here's a few mp3 samples I made from the recording below. The first two are the same section on the timeline, I just muted each channel and encoded them separately. (I know the mix between the guitar and MIDI track is bad) The third one is both channels together with some talking and guitar, no sequencer:

Guitar & MIDI sequence channel

Mic channel

Talking & Guitar, both channels
Not bad - you're right that the balance between the guitar and the midi track could be better but not bad. The best situation would be if you could record all three tracks individually rather than worrying about the balance of the guitar and backing during the shoot but since you're stuck, not bad.

25 feet on the XLR cable shouldn't be a problem at all - line level balanced cables routinely are run as much as several hundred feet. The voice sounds fine for level, he still may be a little distant or slightly off the mic - try aiming it down a little bit, more towards his upper chest than his mouth - but not distractingly so and as far as level goes you can increase it a tad in post to balance it out with the music track. What are you editing in? Where are your camera's recording gain controls set and what are the meters on the preamp and in the camera showing for his voice?
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Old August 3rd, 2007, 02:50 PM   #30
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Thanks! I was worried because it was hard to listen to in the headphones while recording having two different thing going into each ear but it came out good for a first try. I use Sony Vegas for the editing. The gain level for the mic channel on the camera is 12:00 (halfway point) The gain on the Bluetube for the mic is almost full up (which I don't believe it should be??) The Bluetube makes signals hot as hell so it's weird that I have to turn it almost all the way up to get decent volume into the camera.

As for exact meter levels, I don't recall what they were on the Bluetube, but on the camera I try to keep everything between -12 and 0. I hate buying or watching videos where I have to increase the volume so much to hear it. Plus I usually use the W1 Limiter (http://betabugsaudio.com/plugs.php) (I didn't use it in the clips I posted) to make the audio sound much bigger and better.

For our purposes, I think this setup will be just fine, although I'm sure something is wrong that I have to boost the gain so high on the Tube...
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