Frustrations with wireless Sennheiser system

[Ed Fiebke]

Hello -

I own a couple of wireless (on-camera) Sennheiser lavaliere systems. The specific model is the Sennheiser EW 112P "Camera-Mount' wireless system (A: 516 to 558 MHz). They're used on Panasonic GH5 cameras in a dedicated video-recording "Green Room", set up to record my wife's cooking videos. (The room is painted Chroma-Key Green for keying effects.) The frustrating issue is that I'm getting intermittent bursts of static sounds. I've owned Sennheiser wireless systems for many years and never experienced these short bursts of static sounds until recently. I've tried changing the frequency for the transmitter & receiver. This seems to help, but those static sounds persist, just less intermittently. I also tried changing the lavaliere microphone itself (purchased a new one). Still, those freakin' static sounds persist. I'm guessing that the cause is some kind of radio interference??!!?? It doesn't matter where my wife might be in our home, wearing the lavaliere microphone transmitter. So, whatever is causing the interference is not associated with any one area of our house. Finally, the annoying sound is not associated with movement; it's not the microphone rubbing against clothing. My wife can be standing or sitting perfectly still and the static sound persists. (She carefully places the microphone on top of her head, barely sticking out from underneath her wig. It's a placement "trick" she learned from her theater days.)

Are wireless Sennheiser systems problematic for this kind of issue?!? Any other ideas in problem-solving this issue (hopefully without purchasing a different brand of wireless lavaliere system)??

I do own a couple of boom microphones. But the lavaliere microphone seems to provide the cleanest sound of my loving wife's voice (when there're no bursts of static sounds). I'd like to avoid using a boom microphone. (Our "Green Room" is already crowded with cameras and lighting equipment.)

Thank you for any thoughtful suggestions that you might offer.

In the meanwhile, I hope all are well. . . and all keep well!!

Kind Regards,
Ted

[Paul R Johnson]

Can you put a clip of the noise up? Soundcloud or whatever? The sound of actual interference, co-channel interference, intermod interference and signal strength issues are all quite identifiable. I run many channels of Sennheiser and you get used to RF issues - the old motto is that the most expensive radio mic system is nearly as good as a ten pound XLR cable.

With just one radio in action, the most likely culprit is dead spots and RF 'hole's. Intermod very unlikely with just one transmitter. Interference (here in the UK, I don't know where you are) is most common from TV transmitters and with changes to the band 4G. Sennheiser users often get excited about the band scan, but I have always treated it as useless - it tells you that when you scanned a channel is clear, but that doesn't;t guarantee somebody local is have a Karaoke party an hour later.

How far is the receiver away from the TX? If you are close, then interference must be strong and local. RF noises also get made worse if you have the TX sensitivity turned down, and are compensating in the receiver by turning up. Little 'photos' become BIG 'photos'.

[Rick Reineke]

The EK 100 portable receiver scan is totally inadequate for a populated RF environment. I usually use an RF analyzer to choose a frequency bank. Otherwise, Sennheiser's online frequency finder can ID RF from TV stations in the area which can be a cause of interference,.. lf interference is the culprit . A faulty mic cable can cause ticks and pops as well.

[Chris Soucy]

Hi, Ed...........................

Wiki doesn't mention any airport in your area so Radar is unlikely unless you've just inherited a new (US)AF base.

Have you or yours bought a new mobile device recently (and did this problem appear about then if so) or have you been gifted with a new cell tower adjacent to your back yard?

Try eliminating the RF link and go wired from mic (Lav) to camera. Problem still there? Not your wireless system then.

Last but not least has Congress flogged (sold) your available frequency chunk, or part thereof, to some other user? The Senny web site might give you some guidance tho' if it's an unlicensed user somewhere close you're still sunk.

Regards,


CS

[Pete Cofrancesco]

If you rule out the cable I'd recommend a digital recorder instead. I always have one as backup for these type of issues. Zoom H1 is still the most inexpensive, but if you can spend a little more I'd get the Zoom F2. https://www.bhphotovideo.com/c/produ...2855/KBID/3801

[Paul R Johnson]

Video folk have different needs to the entertainment sector and very different brand preferences. In theatre where I work, Sennheiser is a VERY popular brand and their design feature of many intermod free channels makes it possible to get dozens of channels working happily together, and their software monitoring is very useful to keep everything going. In theatre Lectro products here in the UK are rare, but we see a few in TV and of course Sony are common in TV here but not in theatre! The four digit Sennheiser series are very good in the crowded bands, better than G1,2 and 3 are.

We cannot say what the problem is until we hear it. We’re guessing it’s because of congestion, interference etc, but we don’t know. Most of us will hear a few seconds and immediately know the culprit. RF is one of those subjects that you continually learn and remember. I’ve had an issue in one location where low signal levels seemed the problem, but my Rigol analyser revealed a chunk of the band with strange wide band noise that none of my wide band receivers could hear as noise. If you listen you hear white noise, the nasty hiss. What you don’t notice is the hiss is louder, so the noise just replaces the wanted signal when it drops in the usual nulls. I’ve located the building it’s coming from and it starts at ten am each day and stops at ten pm. My old analyser hid this.

In theatre with tours, you can suddenly have a 14 channel perfectly happy system fail when just one unknown transmitter is turned on. Just two can fail when their intermod performance clashes. I pay a person to stand at a rack and watch a screen and listen. Good value as they hear things start before the audience do. The worst thing is when the broadcasters turn up. Any damn frequency and never a thought to listen first.

[Ed Fiebke]

Hello -

First, I thank you for taking the time to share your thoughtful comments! I appreciate your helping me problem-solve this situation.

I was trying to think of possible causes of for the intermittent static sounds. We do have a WiFi "Mesh" set-up for internet access. It's a system by Eero which acts as a wireless network for our entire home. I wonder if this wireless network system might cause some interference? Also, another possibility might be a cellphone tower that's about 1 1/2 miles from our home. This tower is visible from our front yard. Could cellphone towers also cause interference?

Below is a "wav" file that provides 4 examples of these bursts of static sounds. (I'm hoping that this uploaded file will playback for you!) These examples were captured from a recent video that my wife and I recently did together. Hopefully they'll give more insight to the cause of these static sounds. (Just click on the link to hear the wav file.)

Again, thank you!

Ted

https://www.dvinfo.net/forum/attachm...1&d=1613620102

[Pete Cofrancesco]

Could be either just turn off and what you can control and you'll get your answer.

[Chris Soucy]

Hi again Ed...................

Sure sounds like wireless network polling/ traffic to me.

Plan A:

Simple (hah!) test is to disable your entire "Eero? Mesh" system and see if that solves the problem.
Do note that "disable" means more than using a remote to power a unit to standby. Standby is quite often still polling/ responding. Physically remove power from every single component of the network and any unit that may try to access it, including your phones/ notebooks/ tv's/ DVR's/ tablets/ dishwashers/ ovens/ aircon and the bloody dog.!

Set up and shoot.

Plan B:

Forget the house and take camera/ wireless system/ wife and self to "ElremoteLoc" at least 10 miles from anything resembling civilization as we know it Jim and even further than that from any cell tower, if such is possible.

Set up and shoot.

Plan B at least has the advantage of a nice visit to the sticks which might do something for the blood pressure if nothing else. Do remember to either leave your phones behind or sans batteries and if dog has a networked collar leave it/ them behind as well.

Not much point going into how to resolve the problem till either A or B above has been tried and either fixed the problem or failed to.

Regards,

CS

[Paul R Johnson]

I agree, that’s not any of the usual issues and probably the make of the system is irrelevant. Something is swamping the receiver. I also wonder if that is something sweeping past your frequency and you get the noise as it passes. If this is a permanent location you need to sort, and is always there at any time, I’d google to see if there is a local ham radio club. They have people with the right gear and love challenges. They might find it fun to be Sherlock Holmes and find it. They do crazy things like hide transmitters and then have a competition to be first to find it,

[Ed Fiebke]

Thank you for your sharing your time and thoughts on this issue.

For our next few video projects, I plan on using one of my shotgun mics. It's not necessarily the best solution, but it seems to be the easiest one. Our goal is to "produce" at least one or two of my wife's cooking videos on a weekly basis. (She wants to be a YouTuber.) We're both full-time nurses, often working extra hours for our jobs. So as we plan our time to record and edit my wife's cooking segments, I want to keep things as simple as possible.

I might try turning off our wireless WiFi "mesh" system, though, and see if this might work.

I am sincerely grateful your time.

Ted

P.S. By the way, my loving wife is a great cook! I'm a lucky husband! (I clean up and do the dishes.) LOL!

[Rick Reineke]

What frequency block are your Sennheiser system(s) Ed. I have worked in the capital district with up to four G-100 series systems at a time and can likely recommend a generally clear frequency bank to work in. Of course it could be a very localized, though WiFi is usually not problem. .OTOH, a smart phone in close proximity to the Tx or Rx can fork things up ..

[Ed Fiebke]

Originally Posted by Rick Reineke

What frequency block are your Sennheiser system(s) Ed. I have worked in the capital district with up to four G-100 series systems at a time and can likely recommend a generally clear frequency bank to work in. Of course it could be a very localized, though WiFi is usually not problem. .OTOH, a smart phone in close proximity to the Tx or Rx can fork things up ..

Hi - If I understand your question correctly, I use Sennheiser's A Band: 516 to 558 MHz frequency block.

My wife and I plan on video-recording another one of her cooking segments tonight. I have a "new" audio-recording set-up which involves Sennheiser's wireless lavaliere mic on one track and a shot-gun mic (Sennheiser's MKE 600) on another track. (I'm using Zoom's H6 for the audio-recording device.) I'm going to experiment with configuring higher (different) frequencies for the transmitter & receiver.

I will also make sure that our iPhones are turned off. (I didn't think to do that!! Thanks for the suggestion!)

I've been using Sennheiser wireless lavalieres for years! I've used the rack-mountable receiver versions for live shows - three of them at a time - with never an issue! (My wife and I used to have a nursing & healthcare focused comedy troupe that performed live shows for nursing conventions, years ago.) The issue that I'm experiencing, now, is relatively new. I'm stumped.

Thank you for your response, Rick.

Ted

[Bruce Watson]

Originally Posted by Ed Fiebke

Below is a "wav" file that provides 4 examples of these bursts of static sounds.

RF "hits". Could be from the cell phone tower, but unlikely. More likely is that it's coming from that phone in your hip pocket. You'd be surprised at how much RF spill you can get from a cellphone, even a good one. Cure for this is to "airplane mode" your phones during filming, and put them in another part of the facility well away from you. Yes, hers too. And any others that might be hanging around.

Also, what frequency are you using? Said another way, you did at least check for clean frequencies (even if Sennheiser's on-board software gets no respect) and setup on what at least looks like an empty frequency, yes? Said another way, you aren't just using the factory default setup are you?

I'm asking because I've used Sennheiser G3's in midtown Manhattan halfway up a hotel tower without a problem. I doubt you've got anything like that much RF around your kitchen. I'm just sayin' that it's probably not the Sennheiser system -- it's probably how you're using it.

All that said, wireless is really the wrong tool for this application. Wired will sound better, is way cheaper, and is far, far, far less susceptible to RF interference. XLR cables are made for this, you know? Blocking RFI is their design purpose.

When I was doing a cooking video project years ago, I bought a pair of Oscar SoundTech 802s with XLR converters. Nice step up in audio quality from the Sennheiser G3 kit lav, and another nice step up in audio quality from the Sennheiser radio compander. The radio mics got very little use after client heard this setup. And not a single RF hit over several years of this cooking project.

But if you really want to use radios, you have to set them up properly on a clean frequency and be willing to do that again and again until you find a frequency that works out for you. This *requires* you to monitor on headphones in real-time. You wouldn't record video without looking at the monitor would you? Then don't record audio without monitoring either. Get decent headphones and use them. Every. Single. Time.

If it's really a problem you'll have to get an actual RF analyzer like Rick Reineke suggests. Or... move to Lectrosonics or Zaxcom. But then you're looking at real money.

Oh jeez -- you *are* using fresh batteries, yes? If rechargeables, you're using Eneloops, yes? And they're fully charged, yes? Sennheisers are notorious for not liking low voltages -- they really want fresh alkalines. Cheap rechargeables won't give them the higher voltages they want, but the Eneloops will, if properly charged. This was true of the G2 and G3 line. I doubt it's changed much with the G4s, but I don't have much G4 experience.

[Rick Reineke]

TV channel 27 (548-554 mHz) is 'vacant' in that geographic area, so any of the following frequencies 'should' be interference free .. baring any close proximity RF or physical wiring issues, like a broken lav mic cable. Additionally, avoid having the Tx antenna in contact with bare skin.
G3/4 - Bank 6:
these channels are also inter-modulation free, so you can run multiple systems at the same time.
1: 548,850
2: 549,800
3: 550,250
4: 551,100
5: 551,500
6: 552,150
7: 552,950
8: 553,500
-------
G2 -- Bank-8
Channel 3 = 549,500
Channel 4 = 551,000, or tune to one of the above G3/4 frequencies.,.. these frequencies are also inter-mod free with the G3/4

PS- Most PSMs avoid using 'shotgun' (interference tube) mics in (reflective) environment, a hyper-cardioid ,mic would be a better. 'o
btw, the clip sounds like it could be the mic/cable, (bias current shorting out can produce staticy sounds) try another mic to troubleshoot. As was stated, the OST mics sound darn good at a reasonable cost, and made in USA (central NJ to be precise)