View Full Version : Recording Audio from a Soundboard via XLR?


Travis Cossel
April 20th, 2009, 04:06 PM
I did a search and read through 3 pages of posts and still don't feel like I properly understand how to set this up.

Basically, I'm filming a dance festival and I'm allowed to connect to the soundboard via XLR (100 foot cable). I'm connecting to a Canon XH-A1 and I plan to also have a shotgun mic feed into the Canon XH-A1.

Where do I need to request that this connection be made on the soundboard?

What settings do I need to be concerned about on the soundboard?

What settings do I need to be concerned about on my camera?

For example, on the Canon there is a switch on the XLR box for "line" or "mic", and a switch underneath that for "CH1" or "CH1 & CH2". I'm just not experienced with recording from a soundboard and I'm feeling very confused at the moment.

Garrett Low
April 20th, 2009, 04:32 PM
Travis,

Unfortunately as in most cases there isn't an easy answer to your question. Depending on the type of mixer they will be using and what they will be mixing will dictate what you're going to want. In any case, I don't believe you can use your shotgun and take the board feed. That would require mic on one channel and line level on the other and on the XH A1 I don't think you can do that.

I do a lot of dance/stage shows and when I get a board feed it really depends on the level of expertise of the sound engineer. At a minimum I usually ask for a feed of the soundtrack and if possible also group the MC's mic with it so I get whatever the house is being fed. If the sound engineer is kind enough I'll ask for each of the following in separate groups, the soundtrack feed (left and right), MC's mic, stage mics, area mics. That's a total of 5 channels that I take into my own mixer and then I take that into my camera and simultaneously into a laptop for separate audio recording of each discrete channel. That way in post I can mix the audio.

Now if I can't all of those separate I usually get the soundtrack and MC's mic and record those separately onto a laptop. Then I use my own mics plugged into the camera to pick up ambient sounds and to use for synching cameras and post mixed sound.

Hanno di Rosa
April 20th, 2009, 04:34 PM
1.you need to know the mixers output options. Find out if the mixer is able to feed a stereo mix separately to the XLR inputs of your canon. Set the Canon to line input!
2.I would not use 1 mono mixer-feed and 1 mono shotgun mic.
3. best would be to record the stereo out of the mixer to a separate recorder if you want to use a stereo mic and synchronize the audio from the external recorder in the timeline of your NLE with the shotgun.

Travis Cossel
April 20th, 2009, 05:08 PM
Thanks for the info, guys.

So I've heard some stuff here and there about making sure the feed to the camera isn't too hot. How do I do that? I know the XLR box on the camera has an att. switch, but how do I know if that needs to be on or not? Do I just start with it on and adjust the levels on the camera?

EDIT: just read in the manual that the ATT switch only works when the XLR is set to 'mic' mode. Won't have any affect in 'line' mode.

Steve House
April 21st, 2009, 03:45 AM
Note too that depending on how far your camera is setup from the stage, the board feed will arrive at your camera far sooner than the sound wave that's hitting your shotgun mic. If you later try to mix them in post you could experience signifigant problems with reverb due to the arrival time differences. Roughly each 30 feet of subject to camera distance corresponds to a time lag of 1 video frame.

Don Palomaki
April 21st, 2009, 04:59 AM
As implied above, your post has too little information to give a detailed answer.
Need information on the soundboard, its output, your shotgun mic, and several other issues.

The best bet is to use an external recorder to record the signal from the sound board. That way you are not tethered to the board, and do not have to worry about long cables, etc.

If you want to use both the board feed and your mic, they should be reasonably closely matched in levels. Also, be aware that if you use auto gain control, the louder source will effect the level of the other source. And you may may want to use an isolation transformer with ground lift capability as well, especially if you are using A/C power for your camcorder or any connected gear.

Test the overall setup well before the event if you can so you have time to resolve any problem that you may discover in the test process.

Sam Mendolia
April 21st, 2009, 06:07 AM
Get yourself a Beachtek, or similar device, that will take in two different audio signals, in your case a line level on one channel, and a mic level- your shotgun, on the other channel.
The Beachtek will output the correct signal to your videocamera.

You can control gain on the beachtek, and all will be good in your audio.

Brian Larson
April 21st, 2009, 08:32 AM
HI,
one of the best ways to get a good controlled mix from the mixing console is to plug into an unused AUX send. the AUX send on most mixing boards is balanced. if it is a 1/4 inch TRS connection, and your camera accepts an XLR connector then just get a TRS to XLR converter and use a 100 foot microphone cable with XLR terminations.

Using the AUX send from the mixing board gives you way more control over the mix you are getting from the console, you can then easily set up a mix minus situation, say if you want just the microphones and not the background music, then just turn down the channel with the music.

also the AUX sends can be set up to give you pre-fader and pre-EQ levels, this will let you have a signal source that is not being manipulated by the sound guy, meaning that if he pulls down a fader, you will still get the audio from the channel, and if he messes with the EQ to compensate for room acoustics or his personal taste, you signal will not be affected and will be "flat" with no EQ added to the signal.

the AUX send will also give you a variable level that you can control so you can set up an optimal "Line level" signal level for your camera.

so set your camera to line level, have the sound guy send a tone and adjust your line level in on the camera so that the tone registers 0db on the audio meter.


hope this helps.
cheers!

John Peterson
April 21st, 2009, 08:39 AM
Is your line input on the camera at -10dB or +4dB?

You may want to send the soundboard feed into a separate recorder and record using your built in or external mike from your camera just to make sure. I run separate mikes from the stage and generally don't use a soundboard feed. A lot of that has to do with the soundboard operators and the rest with lack of control at my end.

John

Chris Rackauckas
April 21st, 2009, 10:41 AM
An Aux is one way to do it, or if the board has it you can use a matrix. A matrix is the same thing basically except it lets you take a mix from the submasters, but you can boost/cut whichever submasters are needed. Same deal basically though, but less control, but easier to control.



BIG NOTE!

Remember to bring a XLR-TRS though, most boards do not have AUX outs that are XLR. It's good to have around because you might be an unlucky one.





And for this... since you are using a line level signal, not a mic level signal, you set it to line. If you need to use a mic, put an inline attenuator on the line level signal of -30 or -40 (you can get it cheap from naiant online), and then you have it at mic level so you can set your XL-A1 to mic and use both the board and the mic.

Travis Cossel
April 21st, 2009, 10:53 AM
Note too that depending on how far your camera is setup from the stage, the board feed will arrive at your camera far sooner than the sound wave that's hitting your shotgun mic. If you later try to mix them in post you could experience signifigant problems with reverb due to the arrival time differences. Roughly each 30 feet of subject to camera distance corresponds to a time lag of 1 video frame.

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?

I have 2 Olympus DVR's that I could use to record audio. I could hook one up to the soundboard. Do I need to worry about the signal from the soundboard being too hot for the DVR?

By the way, thanks to everyone for the information. I wish I could give out more info on the soundboard but I've never seen it and don't have any other info yet. I can contact the board operator for the event but I would need to know what questions to ask him first.

Brian Larson
April 21st, 2009, 10:55 AM
an ideal option would be to take an AUX send or a matrix like Chris suggested and run that signal to a Mackie 1202 or other similar board. then take the 2 channel master output from the 1202 and run it to your camera.

this will let you use the microphone channels for your own microphone array and will give you a great control surface for your audio and will let you insert a delay to keep your microphones insync with the stage microphones.

Travis Cossel
April 21st, 2009, 12:14 PM
I only have a little Nady 4-channel audio mixer, which has all 1/4" inputs and no XLR. I wasn't planning on using it because I figured it would just degrade the audio signal (ie - more connections). Would I be better off running sound from the board through this little mixer to my DVR, and then use a shotgun on the camera to capture house ambient audio?

The trouble is that I can't run the shotgun and the soundboard feed to my camera at the same time, and I don't have any room in the budget to purchase additional equipment.

Brett Sherman
April 21st, 2009, 12:45 PM
I'm not sure I've ever run into a situation where the line level coming out of the mixer is too hot for the line level on the camera. Actually, it's almost always the opposite because they are pulling down the master fader to get the audio at the right level for the PA. Plus many mixers 0db is actually somewhere between -10db and 0 db not the +4db that your camera expects. You end up with a line level that is too low to be usable. So I almost always use an XLR pad to get the level down to mic level -- that gives me the gain I need for a decent level on the camera. So my advice would be to bring an adjustable XLR pad. Also you'll want a 1/4" to XLR adapter with a transformer because many Main Outs and Aux Sends are 1/4" and a RCA to 1/4" adapter in case you have to plug into the tape output of the mixer.

Sam Mendolia
April 21st, 2009, 12:49 PM
Can you get an adaptor for your shotgun, and run it into your Nady?
Also run the soundboard audio to the Nady.
This will give you control of what sound level, from which source, gets to the camera.

Sam Mendolia
April 21st, 2009, 12:54 PM
Once again, the Beachtek would allow you to plug in fromthe board, and use your shot gun.

Travis Cossel
April 21st, 2009, 12:59 PM
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
April 21st, 2009, 01:04 PM
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
April 21st, 2009, 01:25 PM
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
April 21st, 2009, 01:25 PM
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
April 21st, 2009, 01:36 PM
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/HDV/XHA1/images/audio_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
April 21st, 2009, 01:36 PM
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
April 21st, 2009, 01:51 PM
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
April 21st, 2009, 01:54 PM
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
April 21st, 2009, 01:57 PM
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
April 21st, 2009, 01:58 PM
yep - that sounds fine. With all this kit you should have what us brits call 'belts and braces'.

Travis Cossel
April 21st, 2009, 02:03 PM
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
April 21st, 2009, 05:28 PM
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
April 21st, 2009, 05:45 PM
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
April 21st, 2009, 08:48 PM
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.

dB dBu dBV to volts conversion - calculator volt volts to dBu and dBV dB mW - convert dB volt calculation online attenuation loss gain ratio reference audio engineering dBFS dBVU 0 dB converter - sengpielaudio Sengpiel Berlin (http://www.sengpielaudio.com/calculator-db-volt.htm)

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