Multi-Notch Filter: Why 3 Not Working?

[m718]

how come more than one noth filter doesn't work. I Have three 60hz filters that have 12 db attenuation each when used one at a time but when I put them one after another in the circuit only the first works. all connections are proper I made the circuit many times because I thought I was doing somthing wrong.

 

[vk6kro]

Sounds like a load problem.

Load is an important factor in filter design, so you would need to consider how the input of the second filter looks to the output of the first one.