How to Prevent Echo'y Voices on Wireless Lavs during the Ceremony?

[Edward Calabig]

I'm having an issue with my Sennheiser Wireless G3 Lav mics. I'm using a pair on the officiant and groom and the echo sometimes comes out with echo/reverberation on some locations. I have put a windscreen on both lavs.

How do I prevent this? Are there any wired recorder systems that are recommended that I can just attach to the subjects rather than dealing with wireless mics?

[Don Bloom]

Is the echo from the PA system in the church? Sometimes the PA systems they use aren't the best and the size and hard surfaces cause an echo that is hard to get rid of. The other thing might be the fact that both mics are picking up what's said and causing it. It could also be the placement of the mic on the people. Not close enough to the mouth. I would test the systems you're using in a non church setting such as your own house just to have something to compare it to. If you don't get an echo there then perhaps it's just the church(es) themselves. Big, hard surfaces, not great PA systems will all combine to mess your audio up.

[Dave Partington]

Originally Posted by Edward Calabig

I'm having an issue with my Sennheiser Wireless G3 Lav mics. I'm using a pair on the officiant and groom and the echo sometimes comes out with echo/reverberation on some locations. I have put a windscreen on both lavs.

How do I prevent this? Are there any wired recorder systems that are recommended that I can just attach to the subjects rather than dealing with wireless mics?

It's really simple. Each mic is closer to the person speaking and further away from the other one. Sound travels at a relatively slow speed, so you will always have an echo between the two mics because they will effectively be out of sync. Maybe it's a frame, 2 frames or perhaps sub frame, but it will be there and there is NOTHING you can do about this on the day, other then have them stand really closely together (not going to happen!).

So, you get around this be not having both mics active during the same time following the edit. Fade between them as required during the vows / rings and fade the groom's mic to silence when ever he is not speaking.

Wind screens won't have any effect on this at all. It's a simple law of physics. The further apart they stand, the worse the echo. If you're having trouble fading between them during the vows then it may be a good time to fade to the groom's mic and leave that one active instead of the officiant. You'll lose some efficient clarity but it's better than them each echoing.

[Robert Benda]

They're right. If the echo is a 2nd person appearing on your lavs, make it closer, and turn it down OR stop doing 2 wireless mics into one camera. This fight (along with signal interference, dropout, and delay) are why we opted for pocket recorders.

[Don Bloom]

I meant to include this in my earlier post but got distracted (mean at my old age I forgot)

If it is that the "echo" is coming from the second mic, can you set the audio track in your software to left only and right only?

On occasion I have that problem and by selective cutting I can switch from left to right only which takes care of the problem and gives a nice clean channel to work with. BTW, I use Vegas so I'm guessing that it can be done in other software.

[Dave Partington]

Originally Posted by Don Bloom

If it is that the "echo" is coming from the second mic, can you set the audio track in your software to left only and right only?

What you really need to do is set them to dual mono and treat them independently, cross fading as required.

[Paul R Johnson]

Pet hate mode on.

A frame's worth of delay is a BIG distance. I frame is about 40ft!

We're talking reverberation here, not echo - as in a detectable repeat of a sound. Room sound, if you want to call it that. If the room is reverberant like a church, then you need to maximise wanted to unwanted sound by getting the mic closer to the source, and perhaps cutting down what the mic hears from the room by narrowing the field the mic can hear by selecting a mic with a different response pattern. An omni, too far away will be worst case.Using your lavs just means you are attaching them too far away from the people's mouths, that's all you can do. Remember the inverse square law applies, so a move of just a few inches makes a big difference. Moving the mic from a foot away to 6" doesn't double the output, it multiplies it by 4. The reverberation stays at the same level, making the sound much dryer, because when you reduce the level of the new louder signal, the reverberation and ambience goes down.

Dave's comment about two mics causing problems is valid, because there is phase cancellation when both mics pick up both sound sources. Moving the mics closer helps this one too. We're talking about very small time differences here - far to small to be evident as sync issues, but the weird phasey effect (comb filtering) is not nice. It can be reduced by a gentle pan of each mic to left and right, but mono listeners will still find it nasty.

Just get the mics closer. Think about how the people will stand, and select mic positions as far apart as possible. This means that if a swap from left to right lapel is possible to increase the distance, you should do it. If a person is wearing a suit with a notched lapel, mount the mic there - which is a bit higher than usual but closer. Do check though that its the lapel they will turn towards, not away from.

[Robert Benda]

Just occurred to ask... are these wireless microphones being input into a camera with onboard sound, too?

[Edward Calabig]

Nope these mics are connected to a Zoom h4n. I think I may try moving the mic closer to the source and lowering the input volume next time. Thanks!

[Dave Partington]

Lowering the input volume won't help. It's either there or it's not, and having lower signal to noise ratio is rarely useful in post either. As soon as you add gain in post all the echo your couldn't hear before will still be there.

The simplest way in post is to fade from one to the other as needed so that only one is every being played at any given time.