I've seen resonant frequency being defined as the point where the input signal is in phase with the output signal (So reactance/susceptance is 0).
However conceptually, teaching material seems to link it mostly with maximized output signal width (It's never explicitly stated, just heavily implied: See band-pass filters).
In short, is there any actual link between the resonant frequency and the signal width? Or is the link only there for the special case of RLC circuits?
EDIT: I'm trying to get a general intuition, hence the lack of specifics - but here is the example that got me on this train of thought for context:
I x=>-x--x + | | R1 R2 V | | C L - | | x---x--x
Excuse the ascii art for now, I'll look for something better. (Input: V, Ouput: I)
I was trying to computer the resonance frequency on the above (I have no concrete values), and was wandering if the maximization of the output width (|I|) happens when I and V are in phase; same as a parallel RLC circuit.