Thanks Art and Paul;
The phase of the yamaha in the horn range is of course at the very top or in the + area for most of the horns bandpass area. Where as the woofer section is all in the -side of the screen or bottom for the most part. The phase trace seems to be linear for the most part as well in the horn range. Not going behind in phase as the frequency drops as in the EV speaker.
I wondered if I reversed the polarity would this phase move to the bottom or remain the same just with a problem in the crossover area now. ( I feel this would happen but not sure ) I've measured the yamaha speakers from time to time through the years and they always more or less looked like that.
Douglas,
Paul's tip is helpful, I have reposted the Mackie 1502HD, DSL SH100, and WS8H so you can see the phase response a bit better.
You can see that it is typical for all ported speakers phase to invert towards the port frequency.
It is also typical for phase to generally trend down from low to high, the Peavey is a bit odd in the "up and down" trace.
If you reverse the polarity of a loudspeaker, the phase trace will still look the same, but will be rotated 180 degrees.
The phase traces you posted all look to be OK in the crossover region, but all use different filters to achieve those results.
The phase traces of the speakers I posted all look a bit better, and again, each used very different filters and transducers- there are many different ways to skin the phase cat.
Art