impedance and frequency response relation

[MisterTwister]

look at attached graph. frequency response appears flat, but impedance is rising. shouldn't FR fall as impedance rises?
so I'd expect FR to be something like red curve I've drawn.
everything above red curve is cone resonance and seemingly
flat FR is actually a garbage produced by speaker cone.
so I'd never use this speaker above 1k.
does anyone agree?

[MisterTwister]

here is another example. seas excel graph. FR perfectly corresponds to impedance curve, up to 5khz. there is no cone produced garbage up to that point.

[ChrisA]

Originally posted by MisterTwister
look at attached graph. frequency response appears flat, but impedance is rising. shouldn't FR fall as impedance rises?
so I'd expect FR to be something like red curve I've drawn.
everything above red curve is cone resonance and seemingly
flat FR is actually a garbage produced by speaker cone.
so I'd never use this speaker above 1k.
does anyone agree?

Originally posted by MisterTwister
here is another example. seas excel graph. FR perfectly corresponds to impedance curve, up to 5khz. there is no cone produced garbage up to that point.

"shouldn't FR fall as impedance rises?" Not really. It requires a LOT more power to reproduce bass frequency at a given SPL than high freq. at the same SPL.

I think you have the separate to cases. If the spike in high freq SPL is due to resonance then you'd expect to see a dip in impedance. My eye sees an SPL to impedance relationship a little highter then yours does. I think as long as there is a relation you are OK. What to avoid (in HiFi stereo loudspeakers) is cone breakup. This is where the code stops acting as one solid mass and becomes "wavey" and flexible. If this occurs I'm sure yu are getting all kinds of added hormonics and phase errors.

[MisterTwister]

so how does one identify breakup in a paper cone?
as I see it. right after first impedance bump usually around 800-1k (for 6-8in woofer) there is one huge cone breakup.
Apparently papers' resonance spreads over long frequency range, which looks smooth when measured.
I thought resonance and breakup are the same thing.
aren't they?