RF and MKH50

[PTA]

For those who use the MKH50, have you ever had RF interference at any given location? This has rarely happened to me, 2 times in 3-4 years, but each time I've plugged in a second mic, my AT4073a, it has vanished. Just seeing if anyone else has experienced this or if I should have mine looked at.

[ProSound]

How old is your 50 does it have gold or silver pins in xlr area

[JesseF]

I'be been using mine for about 18 months with no noticeable RF problems.

[thebrengun]

Yes on a few occasions with both the MKH50 and 60 (the updated, RF proofed editions).  It's not the usual RF from cell phones etc. but rather a kind of whispery sound that would be impossible to type.  For me it has been very low level, only noticeable during quiet takes.  Very infrequent but switching to a different mic will solve the problem and a combination of switching cables and the angle of the boom can help.  For me it has happened with radio towers within line of sight and once filming 12 stories up near the Empire State Building.  I'm only guessing but the problem only occurred on the side of the room closest to the Empire State Building.  Happens to me maybe once a year...

[Whit Norris]

I have had the issue also. An update from Sennheiser took care of the problem.

 

Whit

[RPSharman]

All of mine are either new or have the new chassis with RF resistant feature.

VERY occasionally there's a high-pitch whispery interference. If it happens, I put up a different 50, and it's gone.

Even before the upgrade, the RFI was very occasional.

[Max Hirtenstein]

sending my 50 back for a tuneup and to test for interference. recently noticed a very quiet intermittent bubbly sound, and some also intermittent slight buzzing perhaps from a dimmer. silver pins but updated RF chassis.

[PTA]

Yes, this high whispery noise is definitely what I'm hearing and only on extremely quite scenes.

My MKH is the one with the gold pins and it has only happened to me twice in the past 3-4 years, but good to know others have noticed it too.

Is there a way to tell if you have the RF update? I'm assuming the gold pins is the updated version.

[RPSharman]

All gold pins have upgraded chassis.

I sent in 2 mics for new chassis, not the RF kit, which I found made no real difference, but new $300 chassis. One came back with gold pins and a new s/n plate. The other came back with the same pins and missing s/n plate. Pissed me off a bit, but it works great and I have no plans to sell it, so no big deal.

[BudRaymond]

I had that interference from a video transmitter, Falcon Ultra IIRC. The tech from Sennheiser asked if I worked in a hostile RF environment, to which I replied YES! After the upgrade I haven't had any issues.

[Chris Thueson]

I've had this problem. My 50 is less than a year old. I noticed it in a quiet scene as well, so I swapped out to a 416 because that's all I had as an alternative and the problem seemed to be gone. I listened again once the crew and the lights were gone, swapped cables, and the noise was still there. Must be ghosts.

[jwill]

I have had my MKH 50 for a little over 1 1/2 yrs and have had no issues....I regularly boom it in HOSTILE RF environs like an NFL post game locker room, or even worse on the field post game....never an issue. I switched from my 416 to the 50 because of the locker room environment...lots of reflective surfaces tite ceilings etc...the 50 just works better in side than the 416!

[rich]

what suspensions are you all using? and is the shell of the XLR connected to pin 1?

i have had issues when using a zaxcom plug on tx with a cinela mount that had the shell connected to pin 1. breaking the connection in the XLR reduced things a great deal.

[studiomprd]

 Neutrix RFI connectors on all my poles.= SOP

[Malcolm Cromie]

I've had my pair of MKH50s for about 14 years and the still perform as they did the day I bought them. In about 2001 or 2 I encountered the gentle RF frying sound that Brengun mentioned. This was discussed by many at the time and IIRC there were two popular solutions. 1) Send it back to the factory for new parts and a service or 2) Replace or tighten the screw for the XLR connector as it was thought if it came loose or was fractionally too short it was not earthing properly to the shell of the Mic. I'm not 100% sure of the validity of this explanation but I went with the #2 approach replaced the screw and keep it tight and to this day the problem has not returned.

 

My 02c - Hope this helps,

 

Cheers, Malcolm

[Mark Andrews]

I've had my pair of MKH50s for about 14 years and the still perform as they did the day I bought them. In about 2001 or 2 I encountered the gentle RF frying sound that Brengun mentioned. This was discussed by many at the time and IIRC there were two popular solutions. 1) Send it back to the factory for new parts and a service or 2) Replace or tighten the screw for the XLR connector as it was thought if it came loose or was fractionally too short it was not earthing properly to the shell of the Mic. I'm not 100% sure of the validity of this explanation but I went with the #2 approach replaced the screw and keep it tight and to this day the problem has not returned.

 

My 02c - Hope this helps,

 

Cheers, Malcolm

 

I have one of the older 50's that I bought second hand a while back. I have encountered the whispery/electrical noise only a few times, and through some vigorous testing I noticed that every time the noise appears the back screw (near the XLR connector) has come slightly loose. A quick tighten and the noise disappears. The annoyance is it's such a low level sound, I typically only notice it during quiet takes and it takes a few seconds to get the appropriate allen key out. It's good to know it's not just my mic, and that replacing the screw should do the trick more permanently.

 

~Mark.

[Eric Toline]

I believe that the MKH 50's that were RF modded by Sennheiser have a white round label just above the one of the Allen screws that says CE. There is a top & bottom Allen screw on either side of the XLR. A little bit of clear nail polish will hold them in place after tightening.

 

Eric

[Mark W]

Hey all

 

I've had this issue with my 50s, 1 is 3 & 1/2 years old the other is 1 & 1/2 years old. It can happen on a cable or on Lectro HM transmitter. I swap to a scheops Cmit 5u and no probs. We have a lot of 2.4ghz traffic (focus remotes, red remotes & HD senders) from camera department and a relatively small lighting set up. I notice this problem in 2 sets, it drives me crazy as it seems to be happening more often recently. I'm sending both 50s back to sennheiser for an inspection when we wrap in 4 weeks. I've spoken to our post crew who aren't too bothered by the noise... but it drives me nuts when I end up with it on a take. As we're using Red Epics on our shoot, you can only just hear the actors over the fans during rehearsal, there's no chance you'd hear this noise. As a note, i'm using canare quad cable and neutrik EMC connectors.

 

Cheers

Mark

[Eric Toline]

From tests done with Canare Star Quad & the EMC connectors I know that setup will work with cell phone frequencys. In order to get the best results from the cable & connector it has to be the only cable between the mic & the mixer.

 

 

Eric

[Mark W]

That's all i'm running Eric, I have the MKH 50s in cinela mounts... I can't imagine where the RF could be getting in other than an issue with the mics.

[Eric Toline]

That's all i'm running Eric, I have the MKH 50s in cinela mounts... I can't imagine where the RF could be getting in other than an issue with the mics.

 

 

Then back to Sennheiser for a bench test seems in order. A full list of the details of the RF issues will help them pin point where to look & test. I would be interested in their findings & repairs. and if the problem was solved, thanks.

 

Eric

[Derek H]

Senator, where do you use the Neutrik EMC? Just for the female end at the top of the pole or elsewhere?

[Eric Toline]

Senator, where do you use the Neutrik EMC? Just for the female end at the top of the pole or elsewhere?

If I might offer some test results of star quad cables with EMC's at both ends and at either end. The only end that counts is the microphone end. Adding a cable extention to the EMC cable defeats the results so a 1 foot EMC jumper cable connected to a 24 ft regular cable will not get you the same results as a 25 ft EMC cable. No testing was done with multiple EMC to EMC cables but I believe that it would most likely work.

 

 

Eric

[JesseF]

I feel like I should update my post.  I should say that I never had RF problems until now.  I was doing simple sit down interviews for two days in Midtown Manhattan.  First day everything is fine, the second day comes and I start hearing what sounds like electrical interference on this mic and for some reason my comteks (which worked fine yesterday as well) suddenly lost all range and I had to run a cable and put the 216 TX outside the room less than 10 feet from the receivers to get a decent signal (this was after changing the frequency 4 times).

 

Whatever got turned on the second day was spraying RF everywhere.  No problem though, popped the 416 on the boom pole and all was well .

[Kirill Belousov]

On 8/31/2013 at 5:55 AM, Mark W said:

Hey all

 

I've had this issue with my 50s, 1 is 3 & 1/2 years old the other is 1 & 1/2 years old. It can happen on a cable or on Lectro HM transmitter. I swap to a scheops Cmit 5u and no probs. We have a lot of 2.4ghz traffic (focus remotes, red remotes & HD senders) from camera department and a relatively small lighting set up. I notice this problem in 2 sets, it drives me crazy as it seems to be happening more often recently. I'm sending both 50s back to sennheiser for an inspection when we wrap in 4 weeks. I've spoken to our post crew who aren't too bothered by the noise... but it drives me nuts when I end up with it on a take. As we're using Red Epics on our shoot, you can only just hear the actors over the fans during rehearsal, there's no chance you'd hear this noise. As a note, i'm using canare quad cable and neutrik EMC connectors.

 

Cheers

Mark

Shooting with two Red Dragons, Amor 6 Teradecks, 2 remote focuses, 2 remote iris controllers, bunch of wireless. 

 

Occasional we have started experiencing this shimmery quiet noise few weeks ago. Can't figure out what causes it. We change frequencies and out goes away. Then grew weeks latter out comes back again. Using MKH50 with Lectro HM buttplug. Going into 688