Original poster: Steve Conner <steve@xxxxxxxxxxxx>
I heard him say
that, using only PASSIVE RC circuits, it was possible to synthesize any
transfer function shape
I don't believe it! Some transfer functions need complex poles, and
RC circuits can only give real poles no matter how many you string
together. The "classic resonance curve" Jim Lux mentioned is the
simplest example of a transfer function that can only be made with
complex poles.