I ran a bruco yesterday that showed lots of low-ish broadband coherence of SRCL, PRCL and MICH.

I have a previous good measurement of the PRCL coupling, so I used that to iteratively fit an improved feedforward. Based on the last test I did of the PRCL feedforward, I am not certain that just adjusting the gain is good enough right now to reduce the coupling significantly. screenshot

I also measured and tried to fit a better SRCL feedforward. The challenge continues to be fitting the low and high frequency behaviors of the SRCL coupling simultaneously. The misfit of the high frequency behavior continues to create a broad bump of SRCL noise around 100-300 Hz.

I made some small improvements of the SRCL coupling, but there is still room for more improvement. screenshot

I still need to remeasure and refit the MICH feedforward.

The new SRCL FF is in FM6 and the PRCL FF is in FM8. I updated the guardian and the SDF.