J. Kissel, E. Merilh (inspired by conversation with S. Dwyer and G. Mansell)
ECRs E1800233, E1600210
IIETs 11207, 6000

Over the past two Tuesdays, Ed has modified both the ETMY and ETMX Low-voltage, Low-noise [LVLN] ESD drivers (the former last Tuesday, and the later this morning) with the following changes:
    (a) their signal paths upgraded to relax the zeros of the low-noise mode's low-pass filter from ~50 Hz to ~15 Hz (this is ECR E1800233). 
    (b) their power regulation has changed to account for the larger input voltage as a result of the upgrade to the power supply (this is ECR E1600210).
EDIT (indicted by strike throughs): The power supply change has been reverted ... stay tuned for an aLOG from Ed and Richard.

The serial numbers of the chassis are SN1500066 at EY, and SN1500073 at EX. 

I have updated the digital compensation in both test mass' -- repeat, both ETMX and ETMY -- ESDOUTF bank to match the new, relaxed low-pass filter, but only with approximate zeros and poles from the schematic.
The design strings for the new compensation are as follows:
    FM2: "simLP" zpk([15;15], [2.2;2.2], 1, "n")
    FM7: "antiLP" zpk([2.2;2.2], [15;15], 1, "n")
Note that -- just in case -- I've copied over the precisely measured / compensated values for O2 to FM5 and FM10 in ETMY ESDOUTF. This can be deleted once we confirm the upgraded driver works.

Ed has taken transfer functions of these chassis, and uploaded them to the DCC file card for the serial numbers linked above. They need to be processed, plotted, and fit to obtain more precise values for these poles and zeros and then compensated better in order to increase the accuracy of the compensation (I don't know how wrong they are yet, because I haven't plotted Ed's results).