KEF Reference 1 Meta and the vanishing Impedance

Hi everyone,

I have a puzzle and I don't have the money and funds to track it down so was hoping others could chime in. It's not even a piece of gear I own, it's just ... a puzzle.

A while ago a user on Audiogon was complaining about how poor his Kef Reference 1's sounded in the bass. TL;DR: These are 2 Ohm speakers with peculiar impedance curves. At Audio Science Review Erin's Audio posted a great and detailed series of measurements, including this impedance plot. Mind you, this IS a ported speaker:

1683558912262.png


So where is our double impedance hump? Is there an impedance compensation circuit misbehaving here? Poor high pass filter design? A missing shunt resistor value?

I'm wondering if anyone here has an explanation or can lay their hands on one of them to measure the impedance of the two sections independently?

Best,

E