Please help me diagnose this wireless lav problem

A piece of clothing (or something) rubbing against the lavalier?

That might explain why it happens during movement. Might.
 
if we could see the guy moving it would help drastically to diagnose the noise origin. so far it doesnt sound like clothing but more like a radio signal error as if a radar beam passed thru the transmisson ;-)
 
The splat could be one of several things.

It could be a partly broken cable that gets stretched when the presenter moves.

You can check for this by setting up the system on its own and moving the cable around, especially where it exits from the connector and mic.. If it spats when you do this you will have to either replace the mic. or solder on a new connector.


It does not sound like cable-rub to me.

It could be interference from something like a fridge switching.

Also make sure that all mobile phones are switched OFF and not just put on mute or vibrate. A mobile trying to regularly contact the nearest cell can cause problems.

I hope this helps.
 
Sounds like a typical RF dropout to me. Look to make sure you're in line-of-sight, the transmitter and receiver antennas are parallel, the cable from the mic capsule doesn't cross over, go behind, or wrap around the transmit antenna, and no persons or equipment comes between the talent with the mic and the receiver. Check for metal objects on the set that can reflect the signal so as to create multipath issues and move them if you can.
 
If its a drop-out the receiver should squelch out and go silent, not give a splat.

Unless squelch is switched off and the range is very far, of course.
 
Thanks for the replies everyone! The splat has occurred in multiple (every recent) situation and I was able to reproduce it at home with the receiver and transmitter within feet of each other. I'll try and create a video of the problem and post it. You guys are great!
 
shortnstout said:
Thanks for the replies everyone! The splat has occurred in multiple (every recent) situation and I was able to reproduce it at home with the receiver and transmitter within feet of each other. I'll try and create a video of the problem and post it. You guys are great!
Click to expand...

As what did you do that was able to trigger it?
 
Sounds like an RF hit.
In addition to the other helpful tips,

- Always perform an AutoScan.
- If close range, turn up Squelch to High (default is low)
- Position antenna on Receiver Up or Down, not flat
- If far, and if possible, mount Receiver closer to Transmitter via long XLR cable
- Test turning the Transmitter upside down. The clip pops off and inverts easily. Now the antenna can dangle straight down. If it is bent by clothing, or touching skin, you will lose range.
- Check the Sennheiser frequency finder to see if there are any TV stations nearby - move to a Bank further away and AutoScan that bank.

Last but not least consider upgrading to G3. The true diversity system is much better and the Autoscan now goes across all banks instead of just the bank that you currently are in. If all this business about banks is confusing and the manual is not doing the trick, I have a popular video tutorial out there that you might want to watch. Just google for Sennheiser wireless tutorial.
 
Thanks Guy! I loved that tutorial, it saved me many times. Now that I own the G3, I have never been able to find a similar video to help me with the "Gotchas" G2 and G3 are different from the start. any one make a good settings and gotcha video for the G3?

Thx,
Brian
 
This is no doubt RF interference. I had many problems with my g2 wireless transmitter and receiver setup. Is was very unsettling not knowing exactly when this RF "splatting" would occur. I remember last year being asked to look after sound for a conference in a big lecture hall. The people speaking where up in front of the lectern for about an hour at a time. The event was being filmed and my audio was being sent to the cameras, not the in house PA system. (for the PA system the speakers had a separate radio mic on them (not sure of the model). This radio mic worked fine without one RF "splatt". My g2 system however gave me lots of problems. For the first 15 minutes or so it worked fine. But then all of a sudden... "splat". Couldn't believe it! And I couldn't do anything about it due to the nature of the setup and this guy talking about medical procedures in front of 500 people. It was out of my control.
I have since upgraded to the lectrosonics radio mic transmitters and receivers and have not had any problems or nightmare "splats".
 
I call those "RF hits" and I got them more on my G2 than my G3 unit. I try not to point the receiver antennae straight at the talent, pointing forward on the camera. I now put the antennae to the side. I got it more in certain rooms. I even sometimes go it when the presenter shook her metal bracelets when making a point. It seemd a mystery to me because I couldn't reliably re-create it. I even think I have squelch on, and I still hear static. I'm in a small town with few stations and nobody is using wireless when/where I am. I did refer to the sennheiser list of stations and put my channels on unused frequencies. I rarely get hits now, but I hardly ever use the G2. So, still somewhat mysterious...
 
I've gotten a similar noise with my G3 exactly once. I was filming at a food co-op in Portland, OR (don't ask -- long story). I filmed some b-roll in front of the co-op, no problem. Left the mic on the talent, went upstairs to a room over the co-op to teach a class. Did yet another sound check, no problem. Finished setup, waited about fifteen minutes for the attendees to arrive. Final check before teacher started, still fine.

About five minutes into the class, I started to get these "splats" They were seemingly randomly spaced, and could be a single splat like the OP's example, or a series of splats. They seemed to happen most often when the talent wandered to her left toward a window, and under a fluorescent light. But it would happen when the talent was in other parts of the room too.

Needless to say, the class was a loss for me. Never did figure out what the cause was. But... it hasn't happened since. It was a one time deal with my G3.

And just for completeness, I have to add that I filmed more b-roll in Portland the next day in a different location -- again, no problem at all.

The best theory I've heard is that the cause is RF interference from a poorly designed cell phone or pager. That is, one that's leaking RF junk up and down spectrum from its assigned frequencies. The theory continues that the splats are the device hand-shaking with its local cell phone tower.

Another theory was fluorescent light ballast. A dying bulb and the ballast having to kick start it periodically. I'm not sure how a ballast could get to the frequencies the G3 uses though. Hmmm..... probably not a ballast issue, but IDK for sure.

I'm resigned to the fact that I'll never know for sure what it was. And that means that I'll never know when it's going to happen again. Grrrr...

Which just reinforces what we all know more or less. That is, wired is the best way to go. Wireless is always more risky.
 
I know. It's maddening NOT to know the cause. Like I said, my presenter shook her hand once and I got corresponding "splats" that matched her shaking, but also there were random ones throughout the presentation. Over a 2 hr presentation I had to remove 50 - 100 splats, and when it happened on a word, I mixed in my camera mounted mic to at least catch what she was saying. There is another location, a yoga class in an old building from the 1800's, where my G2 and G3 get soooooo many hits. I have to go Lectro to avoid it. Lectrosonics is the splat beater for sure!
 
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