Powered speakers show audiophiles are confused

 There is no practical way to repair a D-class amp.

No but plenty of plate amps with DSP built in to replace it with.

I’m not sure if in this thread I already said it but here:

My main speakers use passive crossover which allows me to use a Luxman amplifier which I love. My next project is a 3-way self-powered center channel. That will allow me to avoid a lot of part soldering, and optimize the components in the time domain, and the final system in the frequency domain while sitting on my entertainment center.

I don’t understand the zealotry of either approach.

The active speaker will be a lot quicker to assemble, and give me time alignment features I need due to the driver arrangment, as well as higher order crossover angles, All of this helps with creating wide-dispersion. My main speakers, by using a single channel per speaker, let me select exactly the sound of an amplifier I want, and keep things simple.

For home, there's no clear cut winner.  In a professional, high power situation there's no contest, line level crossovers and DSP wins every time.

@kota1  - Properly integrated a sub is not directional. 

There are two things to consider when thinking about adding subs:

1. Total output power and dynamic range
2. Response smoothness

If your bass response is ragged due to room modes and you are unwilling or unable to fix it via other means then another sub placed correctly may help, but the placement is driven by the modes you are trying to remove.

I find dogma in this subject unhelpful.  

While active speakers have clear advantages for the designers, and measurable advantages in power efficiency it's clear the markets have decided that there's room for both, with pros choosing active more often than not.

I'm making an active center channel and I'm really not going to be thinking too much about which camp I fall into while listening to my HT system.

Actually, one more thing.  I think people who build speakers have a different perspective on this whole conversation.  If you want to opine with more authority, go build a pair of either. 

Get a kit or design a 2-way from scratch.  Want to do active? Sure, get a 2 or 3 way plate amp and set it up.  Come back and tell us what you've found.

The vertical off-axis responses look wrong.  The vertical drop-off of the top end of the tweeter should be the same or worse than horizontal. 

it seems odd to me that speakers don’t do frequency plots like microphone plots showing off axis coloration at different frequencies.

Meh. How many cars do you see sold with rpm/torque curves?  These aren't lab instruments sold to post-doc researchers. 

OP, looking carefully at the Stereophile measurement plots I think the issue is that the H and V windows are entirely different.

Stereophile uses +- 90 degrees horizontally but a +- 15 degree window for vertical measurements.

Under these conditions the natural tweeter roll off at 30 or more degrees won’t be visible in the vertical plots.  If the GR research video uses the same windows then the same issues will apply.

Normally in the vertical domain speakers perform better in the frequency domain with higher order filters because there's less destructive interference. 

@thespeakerdude Sorry my friend, I don’t care enough about this video to go looking again. If I assume he’s using the same differences Stereophile uses in charting off-axis response then his plots make a lot more sense.

The dip at the crossover region in the vertical plots is quite common, though I seem to remember a Tekton stand mount with absolutely horrible vertical response plots.   If anyone is interested in comparing vertical FR with different speakers.