We have changed the whitening filters in CAL_DELTAL_EXTERNAL_DQ, to the filter described in
We are now using 6 zeros at 0.3 Hz and 6 poles at 30 Hz. Hopefully this will take care of the aliasing problem with DTT, and we can use the calibrated channel when making comparisons with seismic/ sus or PEM channels.
This doesn't impact the GDS pipeline, only CAL_DELTAL_EXTERNAL
No evidence of aliasing in DTT with the new whitening settings.