Bad experience in the field with Lavaliers

P

Papasean

Member
Hey everyone I hope all is well. I need your help or advice, this saturday we were doing test shoot of an interview with someone and here is my simple set up. The A1, two Senheiser freeport wireless presentation set (these are the ones that are UHF and the receivers are DC powered, I now know that I should have bought a mic set up that the receiver is wireless too but I had bought these awhile back before I bought my A1. Oh well.

After setting the A1 on XLR mode and no phantom, we checked audio and it sounded ok. After recording 15 minutes of footage we listen back and the audio was terrible. You could hear us talking but you heard our surroundings along with white noise. I'm thinking the units were too close to each other, which they were and that they were close to metal/concrete which can also mess up transmission. Oh yeah we were at a park downtown and the traffic wasn't that bad but we heard the cars in the audio too. Anyone have any ideas that can help with getting better audio in the field using lavaliers? Thanks.
 
I am not much of an audio guy, but I do know that wireless systems take alot of power. So you double check that your batteries are reliable and at 100% (no knock off brands).
 
This sounds like a really stupid question...but I feel I have to ask..

Are you completely certain you were getting audio from your lavs and NOT from your in camera mic? If you were hearing yourself talking from behind the camera, as well as traffice, etc... it could be that you were recording the wrong inputs.

Also - if its not a tech issues (like input selection or batteries, etc) the issue could be something as easy as mic placement - was the mic put close enough to the talent?
(i'm assuming it was ON the talent - but you never know).
 
Luis Caffesse said:
This sounds like a really stupid question...but I feel I have to ask..

Are you completely certain you were getting audio from your lavs and NOT from your in camera mic? If you were hearing yourself talking from behind the camera, as well as traffice, etc... it could be that you were recording the wrong inputs.

Also - if its not a tech issues (like input selection or batteries, etc) the issue could be something as easy as mic placement - was the mic put close enough to the talent?
(i'm assuming it was ON the talent - but you never know).
Click to expand...

Yeah was regording from the right inputs, the camera mic was disabled because I manually set it on XLR on the A1. And my friend was running the camera about 6-7 feet away from me & the person I was interviewing. So I really thought we were audio but I think it was the receivers were too close and the cables were probably pulling from each other or something. Hmmmmmm... thanks Luis.
 
Hey Daniel J, yeah I had brand new energizer in both units so I don't know what was going on. But I just tested audio again here in my apartment and now it sounds good. Of course I don't have metal concrete slabs, cars and other enviormental sounds going on. Hmmmm... I'm also running one lav setup, I'm going to try testing both mics again to see what happens. Thanks.
 
a couple of things:

make sure phantom power on the xha1 is off. having it on probably won't damage your receivers, but any cable movement may cause heavy distortion.

were each transmitter/receiver on independent frequencies? sharing a single frequency between multiple receivers/transmitters will definitely cause audio distortion.

this is kind of basic, i know, but have you played with the sensitivity setting on the transmitters and the af gain on the receivers? you want to keep your af gain low to minimize noise.

there are lots of ways to place a lav depending on your needs. for hidden lavs, i like to use medical/cloth tape to create a triangle to encase the lav (you can use magic markers to color the tape if necessary), then use topstick or some clear double sided tape to mount the lav to the subject's sternum or cleavage. leave some slack on the cable immediately below then tape the cable down as well.

some good info on lav placement:
http://www.locationsound.com/proaudio/ls/tips/techtips8_4.html
 
henry cho said:
a couple of things:

make sure phantom power on the xha1 is off. having it on probably won't damage your receivers, but any cable movement may cause heavy distortion.

were each transmitter/receiver on independent frequencies? sharing a single frequency between multiple receivers/transmitters will definitely cause audio distortion.

this is kind of basic, i know, but have you played with the sensitivity setting on the transmitters and the af gain on the receivers? you want to keep your af gain low to minimize noise.

there are lots of ways to place a lav depending on your needs. for hidden lavs, i like to use medical/cloth tape to create a triangle to encase the lav (you can use magic markers to color the tape if necessary), then use topstick or some clear double sided tape to mount the lav to the subject's sternum or cleavage. leave some slack on the cable immediately below then tape the cable down as well.

some good info on lav placement:
http://www.locationsound.com/proaudio/ls/tips/techtips8_4.html
Click to expand...

Thanks henry cho, yeah the phantom power was off & the receivers where on different channels. But the gain on the receivers did look a little high. I should have used the volume control on my A1 first, then test to see what differences. Thanks for the cool info also.
 
did you make sure you Mic. ATT was set to on too. I have had a problem with white noice because of the lavs. being to close to each other. The button can be found under the LCD screen.
 
Dcrin3, I just look at that and no it was off. What is the ATT function for, well let me look it up in the manual too. Thanks for the info.
 
You must log in or register to reply here.
Back
Top