Sennheiser MKH-416 Mic High Frequency Problem

[Melody Zhao]

Recently when I use my Sennheiser MKH-416 mic, there is always a boost of high frequency noise (11kHz+, -55dB), which cost me a lot of time and effort in post-production.

So I tried to conduct a experiment, using a K6/ME66 mic to compare with the MKH-416. In the experiment, I used Sound Devices 702T, and made everything else as controlled variables (time / place / direction/ gain/ input terminals… ). However, no matter how the independent variables changed, the high frequency noise was always there.

Have you come across the same problem? Is it an inherent self-noise of MKH-416? Do you know how to fix it?

Please have a look at a picture of the frequency spectrum in the attachment.

Thanks for your answer in advance.

Thanks.