Hello,
We are trying to calculate PSD using obspy.signal.psd.PPSD for accelerometric channels.
Sensor response is loaded from dataless SEED, where original units is M/S**2.
In this case PPSD always assumes the data is in velocity and applying differentiation to the channel data.
So from PQLX we got different results.
From psd.py:
# go to acceleration, do nothing for rotational data:
if self.is_rotational_data:
pass
else:
tr.data = np.gradient(tr.data, self.delta)
It is possible to switch off response correction and also differentiation using is_rotational_data parameter,
but we need to correct response and the data already in acceleration units.
Regards,
Aleksey Emanov