Why is r2 insignificant?
On all first order op amp filters I've seen R2 is used for gain.
Also what second order filter would you suggest?
ust two op amps back to back? or a biquadratic?
Would this be second order?
I am sorry that this has got a bit more complex than answers normally do on this forum but filter design can be quite exacting.
Depending on the op-amp, it will only be able to drive the output within a volt or so of the power supply rails
I take it the use of LM741's will work ok for this?
that opamp is from the Jurassic age