[Elecraft] Setting shift for different filters?

[David F. Reed]

I note that as expected, the center frequency of the bandpass of any 
given filter on SSB seems to be 1.5 KHz, whether its the 6 KHz filter, 
the 2.7 KHz filter or the 2.1 KHz filter.

This seems to work out to be passing from 150 Hz to 2.85 KHz, right?
So the 2.1 KHz filter (without using the shift control) passes 450 Hz to 
2.55 KHz, right?

I note that if I shift the center of the filter down to 1.35 KHz, the 
voices are more intelligible...

When I switch filters and get back to the 2.1 KHz filter, the shift is 
lost; is there a setting I can use to save that shift setting?

Thanks & 73 de W5SV, Dave