Audio advice for recording a lecture at DVinfo.net

Joe Riggs · July 25th, 2012, 05:57 AM

Hello,

I will be filming a panel of 4 speakers and I'm trying to figure out my game plane for recording audio.

I’d prefer to figure out a setup where I could run the mics directly to the camera (to avoid syncing) if possible but since the camera has 2 xlr inputs and this will feature 4 speakers I don't know if that will work.

I guess if the speakers are stationary, we could run the mic feed to the camera or place our mic on the podium. Maybe use a mic splitter? Would a dynamic mic on the podium be the best for this scenario (I have a shotgun, lav, and H4N as well. However, I am willing to rent some audio equipment if necessary.)

Thank you

Noel Lising · July 25th, 2012, 07:49 AM

Joe, since they have 4 mics I assume they have a board/mixer in place, I suggest speaking with the AV guy about getting a feed from the mixer to your camera.

My 2 cents

James Kuhn · July 25th, 2012, 08:28 AM

Ditto...take the feed from the 'board'.

Regards,

J.

Garrett Low · July 25th, 2012, 08:55 AM

Ideal situation would be to have 4 wireless lavs, one on each panel member, and one mic separate mic for audience members questions. That mic could be a condenser or dynamic. Take each mic into a digital recorder all on separate channels. Send the mix from that out to your camera(s) via wireless. The camera mix will simply be for syncing. Keep all cameras and audio recorder running with minimal start stops. That will make synching easy in post.

If the venue is providing mics for the speakers you could pull from the board but then you are relying on someone else who is not focused on getting the best audio for video presentation. Also, if the mics are stationary and the speakers turn their heads the sound will vary greatly. Not as big a deal if you're in the audience but it could be very noticeable on your recording and may even drop the audio levels to where you can't hear the clearly.

I would strongly suggest not to try to get all of the speakers recorded on two channels. You want to have the ability to mix it in post. Sometimes the speakers may talk over each other and if you only have the mix you probably won't be able to get it so that you can understand what they are saying.

Rick Reineke · July 25th, 2012, 09:34 AM

A lot of different ways of approach this and have been covered already. A search on this forum should be useful.

Joe Riggs · July 26th, 2012, 05:23 AM

Thanks for the feedback.

Noel,

I'm not sure they will have a mic for each speaker. I believe they will have a podium with a mic and each speaker will approach the podium to do their lecture.

Garrett Low · July 26th, 2012, 09:24 AM

If they will have a podium that each presenter walks up to and another audience mic you could pull the sound from their PA system. For the easiest in post you could send the audio feed to your camera via wireless. If you have more than one camera you could send it to both cameras over the same transmitter.

For safety, I would put a digital recorder also pulling the sound from the PA system and maybe even consider putting a small handheld digital recorder on the podium if it could be hidden.

I believe in redundancy especially when it comes to sound.

Richard Crowley · July 26th, 2012, 10:34 AM

Quote:

Originally Posted by Joe Riggs

TI believe they will have a podium with a mic and each speaker will approach the podium to do their lecture.

In that case the NUMBER of presenters is immaterial. Only one is speaking at a time. Tap the house system (if there is one, or else set up your own microphone on the podium. Much more straightforward than you made it sound at first.

Shaun Roemich · July 26th, 2012, 03:42 PM

If it is a podium mic, expect at least one presenter to wander away from it muttering the immortal words "everyone can hear me, right? I don't need to use this thing..."

Happens EVERY time. Be prepared for it.

Rick Reineke · July 27th, 2012, 09:24 AM

I'm with Shaun,
There's always some idiot that goes off-mic.
I used to print out a notice to put on the pod and presenters table. This worked much better than word of mouth.. 'in-one-ear-and-out-the-other.'
http://www.dvinfo.net/forum/attachme...1&d=1343402527

Joe Riggs · July 28th, 2012, 08:09 AM

Great info, thanks guys.

I will be tapping into this board and I was told I would need a balanced 1/4 inch to xlr.
Mackie 1402-VLZ3 14 ch. compact mixer [1402VLZ3] - $429.95 : Audio Depot, Madison, WI

The audio guy told me that it will be running "hot", I'm assuming that means near peaking? He also said he can send the signal to me pre or post (I want to say fader but I'm not sure)?

I'll be running that hard wired into the camera (I'll have to do some cable management). Then, my plan was to place an external recorder on stage and a lav near the podium mic or draping off a speaker. What do you think?

Jay Massengill · August 1st, 2012, 01:56 PM

If your camera has a line-level XLR input, then specifically you'll need a balanced 1/4-inch TRS male to XLR MALE cable, then completing the rest of the cable run with regular XLR cables.

However if your camera only has mic-level XLR inputs, you'll need some form of balanced attenuator between the board and the camera.

What camera will you be using?

If the AV person mentioned "pre" or "post" fader send, then they will be using the Aux Sends from the board. Aux 1 is switchable between pre or post fader, Aux 2 is only post fader. Both Aux 1 and Aux 2 send levels are fully adjustable independent of the input faders that are routed to them.

If you want better control of what is being sent to you, your own mixer is really needed between their board and your camera and other recorders.

As mentioned, be prepared for anything and everything odd to happen, so your own high quality ambient mics are important for backup.

Also if you are connecting to AC power at some distance from the house mixing board, be prepared to use some form of safe audio isolation transformer to prevent a ground-loop hum.

Rick Reineke · August 2nd, 2012, 09:09 AM

"Also if you are connecting to AC power at some distance from the house mixing board, be prepared to use some form of safe audio isolation transformer to prevent a ground-loop hum."
Yes, an audio isolation transformer is good in any case.
Regarding AC power, don't run mic cables next to power cables and they should only cross at right angles. though with line level you can likely get away with it.

July 25th, 2012, 05:57 AM	#1
Joe Riggs Regular Crew Join Date: Dec 2005 Posts: 189	Audio advice for recording a lecture Hello, I will be filming a panel of 4 speakers and I'm trying to figure out my game plane for recording audio. I’d prefer to figure out a setup where I could run the mics directly to the camera (to avoid syncing) if possible but since the camera has 2 xlr inputs and this will feature 4 speakers I don't know if that will work. I guess if the speakers are stationary, we could run the mic feed to the camera or place our mic on the podium. Maybe use a mic splitter? Would a dynamic mic on the podium be the best for this scenario (I have a shotgun, lav, and H4N as well. However, I am willing to rent some audio equipment if necessary.) Thank you

July 25th, 2012, 07:49 AM	#2
Noel Lising Major Player Join Date: Jul 2008 Location: Toronto, Canada Posts: 789	Re: Audio advice for recording a lecture Joe, since they have 4 mics I assume they have a board/mixer in place, I suggest speaking with the AV guy about getting a feed from the mixer to your camera. My 2 cents __________________ Noel Lising

July 25th, 2012, 08:28 AM	#3
James Kuhn Major Player Join Date: Sep 2011 Location: Merritt Island, Florida Posts: 865	Re: Audio advice for recording a lecture Ditto...take the feed from the 'board'. Regards, J.

July 25th, 2012, 08:55 AM	#4
Garrett Low Trustee Join Date: Jul 2007 Location: Novato, CA Posts: 1,774	Re: Audio advice for recording a lecture Ideal situation would be to have 4 wireless lavs, one on each panel member, and one mic separate mic for audience members questions. That mic could be a condenser or dynamic. Take each mic into a digital recorder all on separate channels. Send the mix from that out to your camera(s) via wireless. The camera mix will simply be for syncing. Keep all cameras and audio recorder running with minimal start stops. That will make synching easy in post. If the venue is providing mics for the speakers you could pull from the board but then you are relying on someone else who is not focused on getting the best audio for video presentation. Also, if the mics are stationary and the speakers turn their heads the sound will vary greatly. Not as big a deal if you're in the audience but it could be very noticeable on your recording and may even drop the audio levels to where you can't hear the clearly. I would strongly suggest not to try to get all of the speakers recorded on two channels. You want to have the ability to mix it in post. Sometimes the speakers may talk over each other and if you only have the mix you probably won't be able to get it so that you can understand what they are saying. __________________ Garrett Low www.GLowMediaProductions.com

July 25th, 2012, 09:34 AM	#5
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	Re: Audio advice for recording a lecture A lot of different ways of approach this and have been covered already. A search on this forum should be useful.

July 26th, 2012, 05:23 AM	#6
Joe Riggs Regular Crew Join Date: Dec 2005 Posts: 189	Re: Audio advice for recording a lecture Thanks for the feedback. Noel, I'm not sure they will have a mic for each speaker. I believe they will have a podium with a mic and each speaker will approach the podium to do their lecture.

July 26th, 2012, 09:24 AM	#7
Garrett Low Trustee Join Date: Jul 2007 Location: Novato, CA Posts: 1,774	Re: Audio advice for recording a lecture If they will have a podium that each presenter walks up to and another audience mic you could pull the sound from their PA system. For the easiest in post you could send the audio feed to your camera via wireless. If you have more than one camera you could send it to both cameras over the same transmitter. For safety, I would put a digital recorder also pulling the sound from the PA system and maybe even consider putting a small handheld digital recorder on the podium if it could be hidden. I believe in redundancy especially when it comes to sound. __________________ Garrett Low www.GLowMediaProductions.com

July 26th, 2012, 03:42 PM	#9
Shaun Roemich Inner Circle Join Date: Sep 2002 Location: Vancouver, British Columbia (formerly Winnipeg, Manitoba) Canada Posts: 4,088	Re: Audio advice for recording a lecture If it is a podium mic, expect at least one presenter to wander away from it muttering the immortal words "everyone can hear me, right? I don't need to use this thing..." Happens EVERY time. Be prepared for it. __________________ Shaun C. Roemich Road Dog Media - Vancouver, BC - Videographer - Webcaster www.roaddogmedia.ca Blog: http://roaddogmedia.wordpress.com/

July 27th, 2012, 09:24 AM	#10
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	Re: Audio advice for recording a lecture I'm with Shaun, There's always some idiot that goes off-mic. I used to print out a notice to put on the pod and presenters table. This worked much better than word of mouth.. 'in-one-ear-and-out-the-other.' http://www.dvinfo.net/forum/attachme...1&d=1343402527 Attached Thumbnails

July 28th, 2012, 08:09 AM	#11
Joe Riggs Regular Crew Join Date: Dec 2005 Posts: 189	Re: Audio advice for recording a lecture Great info, thanks guys. I will be tapping into this board and I was told I would need a balanced 1/4 inch to xlr. Mackie 1402-VLZ3 14 ch. compact mixer [1402VLZ3] - $429.95 : Audio Depot, Madison, WI The audio guy told me that it will be running "hot", I'm assuming that means near peaking? He also said he can send the signal to me pre or post (I want to say fader but I'm not sure)? I'll be running that hard wired into the camera (I'll have to do some cable management). Then, my plan was to place an external recorder on stage and a lav near the podium mic or draping off a speaker. What do you think?

August 1st, 2012, 01:56 PM	#12
Jay Massengill Trustee Join Date: Jul 2003 Location: Burlington Posts: 1,976	Re: Audio advice for recording a lecture If your camera has a line-level XLR input, then specifically you'll need a balanced 1/4-inch TRS male to XLR MALE cable, then completing the rest of the cable run with regular XLR cables. However if your camera only has mic-level XLR inputs, you'll need some form of balanced attenuator between the board and the camera. What camera will you be using? If the AV person mentioned "pre" or "post" fader send, then they will be using the Aux Sends from the board. Aux 1 is switchable between pre or post fader, Aux 2 is only post fader. Both Aux 1 and Aux 2 send levels are fully adjustable independent of the input faders that are routed to them. If you want better control of what is being sent to you, your own mixer is really needed between their board and your camera and other recorders. As mentioned, be prepared for anything and everything odd to happen, so your own high quality ambient mics are important for backup. Also if you are connecting to AC power at some distance from the house mixing board, be prepared to use some form of safe audio isolation transformer to prevent a ground-loop hum. Last edited by Jay Massengill; August 1st, 2012 at 08:29 PM.

August 2nd, 2012, 09:09 AM	#13
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	Re: Audio advice for recording a lecture "Also if you are connecting to AC power at some distance from the house mixing board, be prepared to use some form of safe audio isolation transformer to prevent a ground-loop hum." Yes, an audio isolation transformer is good in any case. Regarding AC power, don't run mic cables next to power cables and they should only cross at right angles. though with line level you can likely get away with it.