Help with microphones

[CBroholm]

I have a schoeps 641 and an mkh50 that I use with a trx 743. I’ve noticed that when the boom pole gets jostled, there’s a small burst of static and it sounds the same on both mics. I’ve isolated it to the mics and I wanted to see what might be causing this and what I could do to fix this? 

[Johnny Karlsson]

If it's the same with both mics, I think you can conclude that it is not the mics, but rather it's either the TRX, or there might be something going on with your pole's wiring.

[The Documentary Sound Guy]

I think it's fairly obvious:  The mic gets disconnected for a moment when it is jostled and that causes a static burst.  The solution is to immobilize the connection point so it doesn't move or disconnect.  Most boom ops use a bongo tie or something similar to keep the transmitter snug against the boom pole, usually with a piece of foam as a spacer and shock relief. 

[PMC]

Does your boom pole have an internal cable? Simply bypass the boom cable with a temp 12ft cable wrapped around the exterior of the pole and see if the problem goes away.

 

I have to resolder the wee wires at the base connector of my K-tek pole occasionally for this very reason.

[CBroholm]

26 minutes ago, PMC said:

Does your boom pole have an internal cable? Simply bypass the boom cable with a temp 12ft cable wrapped around the exterior of the pole and see if the problem goes away.

 

I have to resolder the wee wires at the base connector of my K-tek pole occasionally for this very reason.

Not internally cabled. Just a jumper cable from the mic to transmitter. Tried it with different cables. Same issue. 

[Jim Feeley]

Maybe the switchable connector cone screws are a bit loose? Or the cable from the XLR connector to the main TX board?

 

Perhaps give Zaxcom a call and they can get it sorted? Though factor in NAB time as you await a response...

[Paul F]

Isolate the problem by eliminating one element at a time.

 

- Both microphones exhibit the issue. On the odd chance that both are the problem, try reproducing the problem with another microphone.

- Eliminate the cable as the problem by connecting the TRX directly to the microphone.

- Eliminate the TRX as the problem by connecting the cable to an extension cable and directly into the mixer.

[CBroholm]

On 4/13/2024 at 5:08 PM, Paul F said:

Isolate the problem by eliminating one element at a time.

 

- Both microphones exhibit the issue. On the odd chance that both are the problem, try reproducing the problem with another microphone.

- Eliminate the cable as the problem by connecting the TRX directly to the microphone.

- Eliminate the TRX as the problem by connecting the cable to an extension cable and directly into the mixer.

Hi Paul, thank you for the suggestions. I tried what you said: 

 

I connected a Sanken CS3 to the TRX and no static was observed when jostled.

 

I connected the MKH50 directly to the TRX and the static was present (when jostled.)

 

I cabled the MKH 50 directly to the mixer via analog input and the static was not present. 

 

I'm left thinking there is some kind of interaction between the MKH 50 and the TRX 

 

I did the same for the 641, except now the noise has gone away. 

 

I then tried another TRX that I connected to the MKH50 and the static was again observed on the MKH 50. 

[Paul F]

3 hours ago, CBroholm said:

I'm left thinking there is some kind of interaction between the MKH 50 and the TRX 

 

But you said you use a short jumper cable normally. So it seems to be pointing more to the TRX, although you don't hear the problem with the 641/TRX. 

 

I'd say the the 'not-solid-lock' of XLRs is the issue. Even though XLRs lock, if there is any sort of jostling, the pins can get jostled and cause noise. I think Documentary Sound Guy has it. The connection probably needs to be secured better.   How do you mount the TRX to the boom?