Gain is limited by gain bandwidth product of opamp.danadak explains the offset well.
That is done at the signal source in Spice. Spice allows you to put a bias on the ac signal. Sin (6,1,100) in the schematic means a bias of 6 volts.
The ac sig. is 1vpp
I think the problem is I am limited to a small amount of gain. I have to take a look a the transfer function for the max amount of gain I can use with this filter.
Thanks for all your responses
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