RF and MKH50

[Bluelobster]

No problems with RF, but I have had my mkh50 succumb to humidity!

[13324]

Had RF interference happen to my three-month old MKH 50 on a set that used Dracast light panels.

[The Immoral Mr Teas]

On 28 September 2018 at 11:34 PM, Bluelobster said:

No problems with RF, but I have had my mkh50 succumb to humidity!

 

Hey, Blue, it would be good to know in what circumstances (extreme?) - I would assume all mics are somewhat challenged by humidity but having lived and worked in the 'tropics' (HK, Thailand, Philippines) I have trusted my MKH, Bruel and Kjaer, and DPA to survive and function.

 

Cheers, Jez

 

And having just noticed New Brunswick maybe it's an extreme cold humidity? So is that the case?

[Bluelobster]

Hey Jez,

 

New Brunswick is certainly not as humid as the tropics, but where I am located can become quite humid in the summer. I had the mkh50 start squealing and give out while shooting an interior scene on a particularly humid day. Had to switch it for the 416 which has proven unstoppable!

 

Cheers,

Blue

[Michael Wynne]

Bringing this topic back to life.  Trying to resolve RF related issues on my beloved 50’s on my current show.  It seems to mostly come from remote RF dimmers on lite mats and or a very busy high RF noise floor modern film set.  Both 50’s are latest model, Allen screw at connector is snug, gold pins all there, etc.

 

My next step is try some jumper cable / connector mods and variations to help further shield the signal from the RF interference prone 50’s .  One thought is use an EMC connector on one end of a jumper that goes to our HMa which is from what I understand a ferrite bead which is simply a low pass filter around 10k.  I could see this solving high pitch buzzing issues but I’m also thinking of the lower swishy/bubbly type sound people have described here that also comes up?

 

Anyone have experience practical advice on RF connector shielding and or EMC connectors.  Or any other solutions that haven’t already been mentioned here.  Also is there such thing as a MKH50 RF tune up at the mothership if they are the newer variety?  

 

 

 

[Joe A]

Michael,

 Try contacting Sennheiser directly through Thomas Gustafson.  He was helpful in directing me for 80xx service last year.

 

 

THOMAS W GUSTAFSON

CUSTOMER SUPPORT SPECIALIST

SENNHEISER ELECTRONIC CORPORATION

860-434-9190 phone

860-434-5349 fax

thomas.gustafson@sennheiser.com

 

[Michael Wynne]

I’ll do it, thanks Joe!

[ProSound]

If your using a internal or external cabled boom pole I would try to mount whatever wireless directly on top of pole next to micorphone 

[soundchris]

Hi Michael, I have worked with mkh50 and -40 wirelessly for a long time and the microfones never had a problem.

To use EMC-Connectors is a good idea, because the connector extends the rf-safe housing of the mic over the open (not shielded) wires.

The gap ind the shield between the mic and the connector is the culprit in most cases because it is not symmetrically wired. (see pic).

cheers

Christian

 

[Marcelo Scofield]

A friend of mine wants to rent my ZMT3 phantom 2 to use with his microphones, a MKH50 and a MKH416.

 

Unfortunately, I don't have a filtered cable (since I rarely use my ZMT3 ph2 as a plugon tx, and when i do, i use with a rf proofed Sanken CS3e).

 

Is there a Sennheiser product model/serial number list in which he could check if his microphones are RF proofed?

[Jason Nightall]

I have a not-very-old MKH50 and noticed RF interference in certain locations that I think was originating from security or CCTV systems in the building. I sent it off the Sennheiser to be looked at and the engineer said it needed a new board which would be £250 to fix. Was a bit annoyed that I had to pay to fix their design fault that they appeared to know about but not own up to, but that lead nowhere. Seems any second hand MKH50 could have this issue. I still wouldn’t get rid of mine though, its one of the best mics I own.

[Ian Berman]

Looks like I’m missing the screws on the XLR connector on my (purchased used) mkh50. As of today, I can no longer plug in a neutrik connector all the way and have it click. 

 

I’ve also been experiencing intermittent rf issues in hostile environments (currently in midtown Manhattan, several floors up). Hoping this could fix it. 
 

how might I go about realigning the XLR connector and sourcing the proper screw? Does it need to go back to Sennheiser? Has anyone done this DIY?

 

thanks

[Derek H]

I had RF issues (buzzing around certain set lighting rigs) on my brand new (2019) 50s and the problem resolved after I re-wired the female ends of the XLR shorty cables. All I did was solder pin 1 to the ground tab. 
 

I’d start there. 

[Ian Berman]

13 minutes ago, Derek H said:

I had RF issues (buzzing around certain set lighting rigs) on my brand new (2019) 50s and the problem resolved after I re-wired the female ends of the XLR shorty cables. All I did was solder pin 1 to the ground tab. 
 

I’d start there. 

Definitely will look into this, but the problem remains that an XLR doesn't lock-in and click anymore. possibly two different issues? 

[Derek H]

Sure

[Matthew Steel]

I only have experience with MKH40's but on those the XLR is rigidly connected to the inner frame, as is the capsule.  So, if the MKH50 is the same way, then as the XLR is pushed into the metal tube/body/shell then the grille/capsule will slide out the same distance on the other end.  Look for that gap at the capsule end and see if it will slide back in to get the screw holes lined up.  On the MKH40 there are springy metal strips on the inner frame that make contact to the outer tube.  I have seen at least one case where an end of one of those had come loose.  It would catch on the inside of the tube making it difficult to get back together.  I'm not sure if it was originally soldered or welded, but my soldering attempt appeared to be successful and then I was able to get it to slide back in.