The end user tested the C636 in studio and found the noise. We then compared with C414 and found more better than C636.
Is there any expert could support us for this issues？ I can share the recording wav files for your reference.
If you look at the equivalent noise level of each mic in the specifications, you'll see that the 414 is rated at 6dB where the 636 is rated at 20dB. Also the signal to noise has a pretty good disparity as well: -88 vs. -74. Both specs are pretty far apart, and may explain the noise level differences you're hearing. I'm pretty sure the 636 is meant for stage and not necessarily studio. Hope that helps.
Matt Ryan - Harman