My question is:

Should the output of driver/s and port/s be considered when selecting an active crossover frequency (AVR, etc.) if the goal is bext phase/time coherence and subwoofer integration?

Are these phase in/differences audible?

Everything I read indicates that a speakers port/s are 360 degrees out of phase (1 cycle of delay) from the driver/s that affect the port/s.

"Since the backwave is already in opposite polarity with the front wave, this inversion brings the two emissions in phase (although the vent emission is lagging by one wave period) and therefore they reinforce each other. This has the useful purpose of producing higher output (for any given driver excursion compared to a closed box) or, conversely, a similar output with a smaller excursion (which means less driver distortion). The penalty incurred for this reinforcement is time smearing: in essence the vent resonance augments main driver output by imposing a "resonant tail" on it."

https://en.wikipedia.org/wiki/Bass_reflex

This leads to the understand that if you are using speakers with ports and a subwoofer/s, you have three sources of output in certain frequency ranges: the driver/s, the port/s, and the subwoofer/s.

This can lead to phase mis-alignment, cancellation, and time-smearing.

http://www.soundoctor.com/whitepapers/subs.htm

Most people seem to agree that fully bung-ing speaker ports alters their behavior in ways that are detrimental, since the driver/s were designed for a ported enclosure.

I have yet to find a speaker review that includes frequency response graphs for ported (un-bunged), partially bunged, and bunged.

Instead of bunging the port/s, it seems that selecting an active crossover frequency (in an AVR, etc.) based on the driver and port output would be another work around.

If we compare the frequency response graphs for speakers, that include the port output, it would lead to me to believe that if we want maximum phase coherence, we should pick the crossover point based on the driver and port output, not the sum of the two.

For example, if we look at the KEF R700 frequency response:

http://cdn.stereophile.com/images/914KEFfig3.jpg

The drivers have 10 db more output at 80 Hz than the ports. This would lead me to believe that 80 Hz would be a fine active crossover setting (AVR, etc.).

For another example, if we look at the KEF LS50 frequency response:

http://cdn.stereophile.com/images/1212KEF50fig3.jpg

The diver has almost 10 db more output at 100 Hz than the port. This would lead me to believe that 100 Hz would be a better active crossover setting (AVR, etc.).

I understand that room acoustics/gain will alter the frequency response. However, the will not alter the ratio of output from driver and port (in my understanding).

Should the output of driver/s and port/s be considered when selecting an active crossover frequency (AVR, etc.) if the goal is bext phase/time coherence and subwoofer integration?

Are these phase in/differences audible?

Thanks,

Aberslam74