Seas P17Re coax crossover evaluation

Got hold of some OEM seas Coax. Woofer is similar to this: http://www.seas.no/images/stories/vintage/pdfdataheet/h0653_p17rextvf.pdf
but in 4 ohms and with a metal dome instead. Built a 10 liter bassreflex tuned to 50 hz.

I am quite satisfied with how they sound, but still on some types of music, I feel something is "strange"

How does this look to those of you who know (I am just messing around... 🙂 )


Seash905crossover.jpg

Black is with tweeter inverse polarity
SeasH905freq.jpg


SeasH905imp.jpg


Is there something strange with this impedance plot?