Recording Audio from a Soundboard via XLR?

[Sam Mendolia]

Once again, the Beachtek would allow you to plug in fromthe board, and use your shot gun.

[Travis Cossel]

Originally Posted by Sam Mendolia

Once again, the Beachtek would allow you to plug in fromthe board, and use your shot gun.

Unfortunately there is no room in the budget to purchase additional equipment for this project. I need to find a way to make things work with what I have.

[Sam Mendolia]

After looking at the camera specs, you can connect the sound board and your shotgun directly to the XLR inputs, and just make sure you have one XLR input switched to line, for the line output from the soundboard, and the other XLR input switched to mic, for the shotgun. If the shot gun is not XLR, then get an adaptor for it, to convert it to XLR.
If the output from the board is mic, make sure your XLR is on mic.

You can then control the levels, for each XLR input, with the audio controls on the camera.

The issue that Steve brought up, can then be corrected in post, if need be, as you now have channel separation.

This camera has all you need to do this correctly, just add the headphones to monitor the sound.

[Paul R Johnson]

One very important feature is to always listen to the mixer input to your camera on some decent headphone that seal out the room sound. Ground loops are really common, and if there is some low level continuous hum, it might not be noticed, and the audio level seems fine. Worth recording a little maybe and checking in a rehearsal or quiet period. The other thing is the level you are being sent. It's pretty certain that what you are being sent at hook up and rehearse time will be what the audio guy thought appropriate at the time. With an audience present, it's very likely he will push the faders even more - which might well raise the level to the point where distortion starts. Whatever level you get at rehearsal, don't push it, leave some spare 'room' where the camera can reduce it a little. I'm not familiar with this camera, so giving it a little space, will allow the auto gain (if your camera has this only) to cope better, and if it has a manual setting and on screen meters, you can have a bit more scope to adjust during the show. To make things worse, it's very common for the levels on the CD or MD the sound op will be playing to vary quite a bit - so depending on how good they are, you could get low or high levels from time to time.

Can I just say something about time coherence, mentioned up a bit. There is of course a delay, but I always find that mixing the camera audio, complete with room sound and live clean sound for dance shows rarely causes problems. For speech, it's a killer, but two or three frames 'wrong' sometimes actually sounds better. The idea of recording the audio and putting it on afterwards is the best way - because you get quality stereo sound, and then you can mix in the 'hollow' weaker, but much more live sound central as a mono source - this gives a nice solid feel, with a live 'essence'. It is always going to be unreal to a degree, but it does sound live. The worse thing nowadays is the damn audiences whooping and even shouting. It's quite easy to lift the applause from one section and lay it over these kind of things - if you do it right, nobody even notices.

[Travis Cossel]

Okay, here's the basic plan I've come up with:

Camera 1 (Canon XHA1 roaming floor on Steadicam Merlin) -----> ambient audio

Camera 2 (Canon XHA1 stationary on tripod) -----> soundboard audio

Camera 3 (Canon HV30 stationary on tripod) -----> ambient audio

DVR 1 -----> soundboard audio

DVR 2 -----> ambient audio


This setup would give me 3 ambient audio sources and 2 soundboard audio sources.

I don't know if it's possible to have the mix coming out of my mixer feed into my XHA1 as a 'mic' feed or not. I don't really understand the difference between 'line' and 'mic'. If I could accomplish this then I could actually run the sounboard feed through my mixer and into my camera via XLR on channel 1, and run my shotgun mic into channel 2. Not sure if this is possible though, because my on-camera XLR box has to be set for either 'line' or 'mic' .. and I don't want to damage it by doing something wrong.

I'm also not sure what the best way to feed the soundboard into the DVR is. I think they have 1/8" inputs.

I really apologize for my ignorance on sound. I film mostly weddings and other projects where sounboards are not involved.

[Travis Cossel]

Originally Posted by Sam Mendolia

After looking at the camera specs, you can connect the sound board and your shotgun directly to the XLR inputs, and just make sure you have one XLR input switched to line, for the line output from the soundboard, and the other XLR input switched to mic, for the shotgun. If the shot gun is not XLR, then get an adaptor for it, to convert it to XLR.
If the output from the board is mic, make sure your XLR is on mic.

You can then control the levels, for each XLR input, with the audio controls on the camera.

The issue that Steve brought up, can then be corrected in post, if need be, as you now have channel separation.

This camera has all you need to do this correctly, just add the headphones to monitor the sound.

Thanks for your continued help on this. The XLR box on the XHA1 has a single switch that can be set to either 'line' or 'mic'. The manual doesn't go into detail on how this works, but I'm assuming that when you set the switch the setting applies to BOTH of the XLR inputs. In other words, if I set the switch to 'line' then both XLR inputs will be set to 'line'. Here's an image of the XLR box:

http://www.usa.canon.com/app/html/HD...udio_img01.jpg



The shotgun mic is an XLR mic, to answer that question.

So maybe the best idea would be for me to request a 'mic' output from the soundboard so I can have the XHA1 XLR box set to 'mic' and take a feed from both the soundboard AND the shotgun mic?

[Paul R Johnson]

The mixer will have outputs on xlrs balanced (only on bettter ones), 1/4" jacks - probably unbalanced, so ok for your dvr, or as phono type hif-fi sockets, also unbalanced and fine. You just need the correct cable.

Mic and line difference is twofold. One - line is a higher level signal, often unbalanced - which is fine. It's the kind of level that comes out of a CD, or DVD audio output, it's nearly a volt. Microphones don't produce anywhere near this level, they're down in the millivolt area for many - so sockets designed for mics have lots more gain. This means that bunging in nearly a volt produces horrble distortion. It rarely damages anything, but sounds dreadful. It works in reverse too, sticking a mic into a line level input, even if they have the same connector, won't produce much, if any sound.

Mics are also usually balanced, on xlrs - the idea being that as the signals are weaker, they need more care to protect them from interference - something a balanced circuit is good at. unbalanced connections are more susceptable to interference and unwanted noise, but if the level they are carrying is higher - it often doesn't matter.

Just to confuse things, watch out for guitars. They are higher level than mics, but not as high as a proper line level. Handy to know if you ever need to work with them.

EDIT
if you want a mic level output from a sound mixer, you will need (or they may have) a gadget called a DI box, this has line level in, and mic level out.

[Garrett Low]

Travis, given the equipment you have available I would take your two Olympus recorders and get pre-fader, pre-EQ feeds from the board. Then, if you can, take two mics into your A1. You mentioned that you have one Shotgun mic but if you could get (barrow or rent) a pair of small diaphragm condenser mics. For concerts these will give better overall sound than your shotgun.

Then, take all the sound you've recorded and in post see what the best remix you can come up with is.

[Travis Cossel]

Paul, thanks so much. I'm starting to understand some of this now. Basically, if I want to use the shotgun mic I need to set the XLR box to 'mic' input, which means I would need a 'mic' output feed from the main soundboard to avoid distortion. I've sent an email to the sound tech to find out if this is possible.

And for the DVR's I basically just need an unbalanced 1/4" feed from the soundboard attached to the DVR using a 1/4" to 1/8" adapter, right?

This is a big arena so I'm assuming the soundboard is pretty advanced .. not like a tiny church board.

[Travis Cossel]

Originally Posted by Garrett Low

Travis, given the equipment you have available I would take your two Olympus recorders and get pre-fader, pre-EQ feeds from the board. Then, if you can, take two mics into your A1. You mentioned that you have one Shotgun mic but if you could get (barrow or rent) a pair of small diaphragm condenser mics. For concerts these will give better overall sound than your shotgun.

Then, take all the sound you've recorded and in post see what the best remix you can come up with is.

Again, I don't have any room in the budget at this point to rent or buy anything. Thanks for the advice on the DVR feeds.

This isn't really a 'concert' by the way. It's a dance festival, which means I'm assuming all of the music is being played by the sound crew via CD or whatever. I don't anticipate any instruments or anything. I just need to make sure I've got the music and anything spoken.

[Paul R Johnson]

yep - that sounds fine. With all this kit you should have what us brits call 'belts and braces'.

[Travis Cossel]

Originally Posted by Paul R Johnson

yep - that sounds fine. With all this kit you should have what us brits call 'belts and braces'.

I might need an interpretation of that, lol.

[Steve House]

Originally Posted by Travis Cossel

Interesting. I didn't realize that. So that means the sound feed from the XLR to the camera is going to be off from the video as well?

Nope, you'll be fine for that. Video will arrive from the stage at the speed of light. Sound from the board will arrive virtually at the same time assuming the board's sources (mics and such) are on the stage. But sound traveling through space from the stage to a mic at the camera will arrive later by about 1 frame for every thirty feet of separation between the source and the camera.

[Travis Cossel]

Originally Posted by Steve House

Nope, you'll be fine for that. Video will arrive from the stage at the speed of light. Sound from the board will arrive virtually at the same time assuming the board's sources (mics and such) are on the stage. But sound traveling through space from the stage to a mic at the camera will arrive later by about 1 frame for every thirty feet of separation between the source and the camera.

Thanks, Steve. Actually, right after I posted about that I realized I misread/misunderstood your other post, but the thread was moving fast so I just left it alone.

[John Peterson]

I believe the Canon XHA1 has a 6dBv input. That would be hotter than the line level standard value by 4 Decibles. 6dBv = 8.2 dBu - a difference of 4 less than standard line level.

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What the Canon sees as the nominal input is probably higher than many other cameras forcing you to turn the controls way way up depending upon what you connect it to.

You may want to try Mic + Attenuation using the Mic setting instead of the Line setting.

John