Removing Instrument Response - Velocity or Displacement for beamforming

Usage Questions
1

Hi, I am looking to carry out some beamforming to determine the incoming direction of secondary microseisms in a frequency range of 0.125-0.5 Hz. I am a bit confused about how to remove the instrument response in the proper way without introducing artefacts.
I am currently removing the mean and linear trend (from each 2-hr time series) followed by pre-filtering before converting to displacement with remove_response and finally resampling to 1 Hz (from 50 Hz). Is this the correct order of processing steps, and I am also confused as to whether I should be converting to displacement or velocity (have seen both done in papers on the subject).
Thanks, here is the code.

n=0
Archive='/raid1/ds784/trash/' #path to where data is stored
st = Stream()
for file in sorted(glob.glob(Archive + '3_clean_data_2/'+'*HZ*')):
        n=n+1
        try:
            #extract file name and path
            filename=file.split('/')[-1]
            print(filename,n,"/",len(glob.glob(Archive + '3_clean_data_2/'+'*HZ*')))
            outpath=out_dir
    
            #read in file
            st = read(file)
            print(st)
            st_copy=st.copy()
            
            #demean and detrend data
            #st_copy.plot()
            st_copy.detrend("demean")
            st_copy.detrend("linear")
    
            pre_filt = [0.04, 0.08, 10, 20]
            #Remove instrument reponse

            st_copy.remove_response(output="DISP", inventory=inv, pre_filt=pre_filt, zero_mean=False, taper=True)
            #st_copy.plot()
            
            st_copy.resample(1)
            #st_copy.plot()
            #merge gaps
            #st_copy.merge(method=0, fill_value='interpolate')            
            
            #write out file (over-writing original)
            st_copy.write(outpath+filename,format='MSEED')
            print('writing: ',outpath+filename)
        except:
            print('failed on file:', file)
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2

Hi, I think most common is response removal to velocity, because that is the observable modern seismometers record.

For resampling you can use the decimate method, which is sufficient in your case.

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