Sennheiser EW 112P noise problem

[Neutie]

Hi,

I have a question regarding audio recording with my Sennheiser EW 112P G4-B. I am using this one regularly for spoken word on location. When standing quite nearby, I have no problems 99% of the time. But when taking a bit of distance to my subject (say 20 meters), I get this noise/interruption, as you can hear here:

https://easyupload.io/m/hdf12b

However, it's not all of the time. In the exact same spot, the noise is sometimes more than other times. I know it's not clothes touching the mic, since the problem does not occur closer by. I don't know how to fix it. I have tried changing the frequency a couple of times. Are there other things I am unaware of? The reach should be around 100 meters, but most distance I've covered is maybe 25.

Thank you!

[Hugh Robjohns]

In my experience a range of 100 metres is only likely in perfect conditions out of doors. And even 25 metres can be optimistic if there's a lot of metal work around -- which is common indoors, of course. (Metalwork obstructs and reflects RF signals, causing brief signal dropouts).

The noises in your examples sound like typical RF dropouts to me.

Were you moving or turning your body at the time? Both can affect the signal path between transmitter and receiver.

The EW112P is slightly hampered by not having diversity reception, so will inevitably be more prone to RF drop-outs than higher-spec'd systems.

The best I can suggest is to arrange for the receiver to be as close as possible to the receiver, with a direct 'line-of-sight' and nothing metal in-between.

Place the receiver as high as possible, with the aerial well clear of any metal fixings, and well away from any digital audio/video equipment and associated cabling if possible (the latter might not be more challenging if it is camera-mounted, of course!).

For the transmitter, try and make sure the wearer has nothing metallic (keys, coins etc.) near the aerial, and ideally not in his/her clothes at all!

Try and mount the transmitter to keep the aerial as far away from the skin as possible, and avoid winding the mic cable around the transmitter and/or aerial.

Hope that helps.

[Neutie]

Hello Hugh,

Thanks so much for your reply!

In this case, we were filming in nature, with a direct line of sight. However, the subject was indeed walking while talking and I may have noticed that having smartphone and other stuff in pocket might not help the signal as well.

The transmitter is fixed on the belt on the back of the subject, the mic wire then going under the sweater to the mic. The excess of cables are then put in the back pocket, next to the receiver. Should I try to put the cable further away from the transmitter? Also, sorry for asking, what do you mean by 'the aerial'?

The receiver is mounted on top of the camera.

Lastly, maybe for future purposes, would you recommend any set to do this kind of work that might have less of these problems (by having the diversity reception as you say)?

Thanks again. Cheers!

[Hugh Robjohns]

I may have noticed that having smartphone and other stuff in pocket might not help the signal as well.

Absolutely! I should have said; definitely remove mobile phone from presenter while using the radio mic!

...sorry for asking, what do you mean by 'the aerial'?

It's an alternative term for the antenna -- the short stiff rod that sticks up from the transmitter and receiver units to send and receive the radio signal.

The transmitter is fixed on the belt on the back of the subject

The key is to try and keep the aerial/antenna as far away from the skin as possible. You could try clipping the transmitter onto the belt upside down, so the aerial points down instead of up, or even sideways if the clip allows it. Or try slipping the transmitter into a front jacket pocket (so there is less flesh between transmitter and receiver!)

Should I try to put the cable further away from the transmitter?

It won't harm to try. I have known it to make a difference on occasion...

The receiver is mounted on top of the camera.

Make sure the aerial/antenna is well clear of the side of the camera -- ideally standing clear above the camera, and in the same orientation plane as the aerial on the transmitter. (Ie. notg horizontal if the transmitter aerial is vertical!)

Lastly, maybe for future purposes, would you recommend any set to do this kind of work that might have less of these problems (by having the diversity reception as you say)?

A diversity receiver is always going to be more reliable, but I don't think Sennheiser still make a camera-mounted diversity receiver, only half-rack sized systems.

So it really just comes down to good practice in fitting the receiver and transmitter, and not getting too carried away with excessive distance between the two. The usable range will also vary with conditions -- I mentioned metalwork in the previous post, but wet trees and ground can reduce range dramatically too!

[Neutie]

Again, thank you very much for your time much for your reply! Definitely going to dive into this.